[SPARK-7848][STREAMING][UPDATE SPARKSTREAMING DOCS TO INCORPORATE IMPORTANT POINTS.]
[SPARK-7848][STREAMING][UPDATE SPARKSTREAMING DOCS TO INCORPORATE IMPORTANT POINTS.]

Updated the SparkStreaming Doc with some important points.

Author: Nirman Narang <narang@us.ibm.com>

Closes #11114 from nirmannarang/SPARK-7848.

tengpeng/spark,shaneknapp/spark,saltstar/spark,map222/spark,liyichao/spark,debugger87/spark,sureshthalamati/spark,mzl9039/spark,taroplus/spark,lvdongr/spark,wangyum/spark,michalsenkyr/spark,metamx/spark,mdespriee/spark,aosagie/spark,jrshust/spark,caneGuy/spark,pgandhi999/spark,guoxiaolongzte/spark,rikima/spark,chuckchen/spark,rezasafi/spark,spark-test/spark,witgo/spark,nilsgrabbert/spark,publicRoman/spark,highfei2011/spark,darionyaphet/spark,jianran/spark,publicRoman/spark,apache-spark-on-k8s/spark,apache/spark,eyalfa/spark,UndeadBaneGitHub/spark,brad-kaiser/spark,narahari92/spark,kissmetrics/spark,mzl9039/spark,vinodkc/spark,WeichenXu123/spark,michalsenkyr/spark,minixalpha/spark,kimoonkim/spark,szhem/spark,holdenk/spark,stanzhai/spark,ericvandenbergfb/spark,lxsmnv/spark,rednaxelafx/apache-spark,guoxiaolongzte/spark,liutang123/spark,bOOm-X/spark,bravo-zhang/spark,Panos-Bletsos/spark-cost-model-optimizer,kevinyu98/spark,yanboliang/spark,debugger87/spark,aray/spark,shaneknapp/spark,metamx/spark,rezasafi/spark,someorz/spark,shubhamchopra/spark,SnappyDataInc/spark,UndeadBaneGitHub/spark,dbtsai/spark,skonto/spark,jlopezmalla/spark,akopich/spark,eyalfa/spark,ericvandenbergfb/spark,rezasafi/spark,minixalpha/spark,rednaxelafx/apache-spark,gengliangwang/spark,vinodkc/spark,witgo/spark,kiszk/spark,mahak/spark,facaiy/spark,ericvandenbergfb/spark,liutang123/spark,darionyaphet/spark,rikima/spark,loneknightpy/spark,mike0sv/spark,adrian-ionescu/apache-spark,SnappyDataInc/spark,lvdongr/spark,wangyum/spark,nchammas/spark,sachintyagi22/spark,wzhfy/spark,rekhajoshm/spark,zhouyejoe/spark,akopich/spark,zero323/spark,big-pegasus/spark,techaddict/spark,Panos-Bletsos/spark-cost-model-optimizer,shaneknapp/spark,ConeyLiu/spark,brad-kaiser/spark,big-pegasus/spark,ueshin/apache-spark,nchammas/spark,poffuomo/spark,cloud-fan/spark,gengliangwang/spark,jianran/spark,shubhamchopra/spark,cin/spark,tejasapatil/spark,mdespriee/spark,zhouyejoe/spark,akopich/spark,minixalpha/spark,guoxiaolongzte/spark,sahilTakiar/spark,markhamstra/spark,spark-test/spark,esi-mineset/spark,jkbradley/spark,wzhfy/spark,bdrillard/spark,ibm-research-ireland/sparkoscope,ptkool/spark,dongjoon-hyun/spark,rikima/spark,stanzhai/spark,wangyum/spark,rezasafi/spark,panfengfeng/spark,bdrillard/spark,taroplus/spark,szhem/spark,Panos-Bletsos/spark-cost-model-optimizer,mzl9039/spark,hvanhovell/spark,michalsenkyr/spark,skonto/spark,cin/spark,publicRoman/spark,debugger87/spark,bravo-zhang/spark,janewangfb/spark,publicRoman/spark,alunarbeach/spark,aray/spark,darionyaphet/spark,bravo-zhang/spark,setjet/spark,caneGuy/spark,chuckchen/spark,JoshRosen/spark,bOOm-X/spark,highfei2011/spark,SHASHANKB/spark,wangmiao1981/spark,adrian-ionescu/apache-spark,1haodian/spark,JerryLead/spark,brad-kaiser/spark,ron8hu/spark,apache/spark,szhem/spark,jianran/spark,andrewor14/spark,maropu/spark,minixalpha/spark,metamx/spark,aokolnychyi/spark,milliman/spark,byakuinss/spark,UndeadBaneGitHub/spark,markhamstra/spark,Panos-Bletsos/spark-cost-model-optimizer,patrick-nicholson/spark,ueshin/apache-spark,MLnick/spark,map222/spark,witgo/spark,lvdongr/spark,ueshin/apache-spark,someorz/spark,ioana-delaney/spark,map222/spark,icexelloss/spark,xuanyuanking/spark,milliman/spark,ron8hu/spark,icexelloss/spark,jrshust/spark,someorz/spark,ioana-delaney/spark,hvanhovell/spark,stanzhai/spark,kiszk/spark,mzl9039/spark,sureshthalamati/spark,poffuomo/spark,ibm-research-ireland/sparkoscope,highfei2011/spark,jlopezmalla/spark,milliman/spark,joseph-torres/spark,ptkool/spark,loneknightpy/spark,markhamstra/spark,janewangfb/spark,Panos-Bletsos/spark-cost-model-optimizer,jkbradley/spark,kimoonkim/spark,ericvandenbergfb/spark,taroplus/spark,poffuomo/spark,shuangshuangwang/spark,akopich/spark,dongjoon-hyun/spark,HyukjinKwon/spark,joseph-torres/spark,markhamstra/spark,zero323/spark,ddna1021/spark,wangyum/spark,ericvandenbergfb/spark,akopich/spark,big-pegasus/spark,andrewor14/spark,mzl9039/spark,ajaysaini725/spark,huang1900/spark,MLnick/spark,lxsmnv/spark,kimoonkim/spark,rekhajoshm/spark,hvanhovell/spark,MLnick/spark,zhouyejoe/spark,cloud-fan/spark,1haodian/spark,apache-spark-on-k8s/spark,markhamstra/spark,adrian-ionescu/apache-spark,1haodian/spark,mdespriee/spark,skonto/spark,cloud-fan/spark,yanboliang/spark,someorz/spark,ptkool/spark,taroplus/spark,saturday-shi/spark,aosagie/spark,poffuomo/spark,ron8hu/spark,michalsenkyr/spark,nilsgrabbert/spark,adrian-ionescu/apache-spark,bravo-zhang/spark,huang1900/spark,loneknightpy/spark,minixalpha/spark,aokolnychyi/spark,bdrillard/spark,maropu/spark,maropu/spark,map222/spark,nlalevee/spark,andrewor14/spark,mdespriee/spark,zzcclp/spark,jiangxb1987/spark,ericvandenbergfb/spark,nlalevee/spark,darionyaphet/spark,WindCanDie/spark,adrian-ionescu/apache-spark,szhem/spark,wangmiao1981/spark,ibm-research-ireland/sparkoscope,wangyum/spark,Aegeaner/spark,cloud-fan/spark,xuanyuanking/spark,WindCanDie/spark,lvdongr/spark,guoxiaolongzte/spark,JerryLead/spark,hhbyyh/spark,kevinyu98/spark,saltstar/spark,big-pegasus/spark,zero323/spark,bravo-zhang/spark,highfei2011/spark,panfengfeng/spark,sachintyagi22/spark,jrshust/spark,goldmedal/spark,vinodkc/spark,ptkool/spark,ahnqirage/spark,chuckchen/spark,mahak/spark,ConeyLiu/spark,tengpeng/spark,sureshthalamati/spark,facaiy/spark,wzhfy/spark,nlalevee/spark,srowen/spark,JerryLead/spark,actuaryzhang/spark,map222/spark,mzl9039/spark,kiszk/spark,janewangfb/spark,nchammas/spark,rekhajoshm/spark,hhbyyh/spark,actuaryzhang/spark,chuckchen/spark,actuaryzhang/spark,SHASHANKB/spark,shubhamchopra/spark,yanboliang/spark,nilsgrabbert/spark,apache-spark-on-k8s/spark,aray/spark,bdrillard/spark,tejasapatil/spark,jrshust/spark,JerryLead/spark,sahilTakiar/spark,jiangxb1987/spark,ueshin/apache-spark,tejasapatil/spark,bdrillard/spark,mzl9039/spark,shubhamchopra/spark,LantaoJin/spark,mdespriee/spark,caneGuy/spark,ioana-delaney/spark,dhruve/spark,WindCanDie/spark,ahnqirage/spark,kimoonkim/spark,darionyaphet/spark,ron8hu/spark,apache/spark,joseph-torres/spark,tejasapatil/spark,huang1900/spark,caneGuy/spark,lvdongr/spark,goldmedal/spark,saltstar/spark,Aegeaner/spark,bravo-zhang/spark,huang1900/spark,holdenk/spark,rednaxelafx/apache-spark,dbtsai/spark,aosagie/spark,liyichao/spark,jiangxb1987/spark,rekhajoshm/spark,hvanhovell/spark,SHASHANKB/spark,LantaoJin/spark,cloud-fan/spark,caneGuy/spark,ddna1021/spark,cin/spark,loneknightpy/spark,brad-kaiser/spark,actuaryzhang/spark,MLnick/spark,bravo-zhang/spark,aray/spark,joseph-torres/spark,SHASHANKB/spark,narahari92/spark,alunarbeach/spark,setjet/spark,dbtsai/spark,loneknightpy/spark,rezasafi/spark,MLnick/spark,srowen/spark,zzcclp/spark,shuangshuangwang/spark,saltstar/spark,narahari92/spark,BryanCutler/spark,dongjoon-hyun/spark,map222/spark,shubhamchopra/spark,witgo/spark,liutang123/spark,akopich/spark,caneGuy/spark,saturday-shi/spark,techaddict/spark,lxsmnv/spark,shaneknapp/spark,zzcclp/spark,spark-test/spark,szhem/spark,jianran/spark,HyukjinKwon/spark,alunarbeach/spark,sachintyagi22/spark,liutang123/spark,esi-mineset/spark,bOOm-X/spark,taroplus/spark,kiszk/spark,ajaysaini725/spark,metamx/spark,tengpeng/spark,huang1900/spark,srowen/spark,ddna1021/spark,poffuomo/spark,ahnqirage/spark,mdespriee/spark,jianran/spark,Panos-Bletsos/spark-cost-model-optimizer,spark-test/spark,skonto/spark,yanboliang/spark,kiszk/spark,loneknightpy/spark,UndeadBaneGitHub/spark,sachintyagi22/spark,milliman/spark,michalsenkyr/spark,hvanhovell/spark,goldmedal/spark,SnappyDataInc/spark,wzhfy/spark,1haodian/spark,ajaysaini725/spark,ajaysaini725/spark,vinodkc/spark,nchammas/spark,xflin/spark,ioana-delaney/spark,techaddict/spark,kevinyu98/spark,pgandhi999/spark,gengliangwang/spark,gengliangwang/spark,darionyaphet/spark,nilsgrabbert/spark,cin/spark,ioana-delaney/spark,huang1900/spark,zero323/spark,shubhamchopra/spark,srowen/spark,mike0sv/spark,zuotingbing/spark,dhruve/spark,ron8hu/spark,sahilTakiar/spark,actuaryzhang/spark,janewangfb/spark,highfei2011/spark,debugger87/spark,ddna1021/spark,aokolnychyi/spark,ahnqirage/spark,LantaoJin/spark,patrick-nicholson/spark,jiangxb1987/spark,JoshRosen/spark,andrewor14/spark,jiangxb1987/spark,facaiy/spark,ueshin/apache-spark,yanboliang/spark,JerryLead/spark,dbtsai/spark,xuanyuanking/spark,yanboliang/spark,shuangshuangwang/spark,wangmiao1981/spark,jlopezmalla/spark,nlalevee/spark,kimoonkim/spark,lvdongr/spark,apache-spark-on-k8s/spark,ericvandenbergfb/spark,narahari92/spark,highfei2011/spark,bOOm-X/spark,nchammas/spark,hhbyyh/spark,publicRoman/spark,hvanhovell/spark,setjet/spark,zzcclp/spark,JoshRosen/spark,jianran/spark,ioana-delaney/spark,Aegeaner/spark,xflin/spark,debugger87/spark,liyichao/spark,ConeyLiu/spark,rednaxelafx/apache-spark,ConeyLiu/spark,cloud-fan/spark,byakuinss/spark,wzhfy/spark,nlalevee/spark,lxsmnv/spark,patrick-nicholson/spark,aray/spark,eyalfa/spark,JoshRosen/spark,panfengfeng/spark,dbtsai/spark,LantaoJin/spark,ahnqirage/spark,srowen/spark,Aegeaner/spark,brad-kaiser/spark,sahilTakiar/spark,JoshRosen/spark,kimoonkim/spark,SnappyDataInc/spark,xuanyuanking/spark,liutang123/spark,guoxiaolongzte/spark,icexelloss/spark,metamx/spark,1haodian/spark,nchammas/spark,guoxiaolongzte/spark,bOOm-X/spark,apache-spark-on-k8s/spark,janewangfb/spark,mahak/spark,shaneknapp/spark,narahari92/spark,dhruve/spark,UndeadBaneGitHub/spark,sureshthalamati/spark,ptkool/spark,zuotingbing/spark,milliman/spark,liyichao/spark,cin/spark,mahak/spark,ron8hu/spark,debugger87/spark,patrick-nicholson/spark,metamx/spark,eyalfa/spark,milliman/spark,maropu/spark,xflin/spark,goldmedal/spark,kissmetrics/spark,techaddict/spark,hhbyyh/spark,apache-spark-on-k8s/spark,jrshust/spark,nilsgrabbert/spark,liyichao/spark,jkbradley/spark,dhruve/spark,mike0sv/spark,SHASHANKB/spark,goldmedal/spark,maropu/spark,rikima/spark,pgandhi999/spark,zuotingbing/spark,narahari92/spark,patrick-nicholson/spark,witgo/spark,adrian-ionescu/apache-spark,chuckchen/spark,sahilTakiar/spark,markhamstra/spark,zzcclp/spark,ibm-research-ireland/sparkoscope,rezasafi/spark,wangmiao1981/spark,saturday-shi/spark,BryanCutler/spark,gengliangwang/spark,ueshin/apache-spark,mike0sv/spark,lxsmnv/spark,holdenk/spark,zuotingbing/spark,WeichenXu123/spark,minixalpha/spark,milliman/spark,sachintyagi22/spark,facaiy/spark,Aegeaner/spark,sureshthalamati/spark,WeichenXu123/spark,byakuinss/spark,yanboliang/spark,wzhfy/spark,JerryLead/spark,mike0sv/spark,goldmedal/spark,setjet/spark,HyukjinKwon/spark,liutang123/spark,WindCanDie/spark,taroplus/spark,mahak/spark,ibm-research-ireland/sparkoscope,Panos-Bletsos/spark-cost-model-optimizer,ahnqirage/spark,stanzhai/spark,szhem/spark,guoxiaolongzte/spark,spark-test/spark,BryanCutler/spark,aosagie/spark,aokolnychyi/spark,actuaryzhang/spark,WindCanDie/spark,gengliangwang/spark,aokolnychyi/spark,bOOm-X/spark,jlopezmalla/spark,WindCanDie/spark,rikima/spark,huang1900/spark,ueshin/apache-spark,joseph-torres/spark,zhouyejoe/spark,big-pegasus/spark,skonto/spark,ahnqirage/spark,WeichenXu123/spark,poffuomo/spark,chuckchen/spark,vinodkc/spark,zuotingbing/spark,matthewfranglen/spark,LantaoJin/spark,rekhajoshm/spark,spark-test/spark,saturday-shi/spark,aosagie/spark,dongjoon-hyun/spark,hhbyyh/spark,esi-mineset/spark,xflin/spark,highfei2011/spark,BryanCutler/spark,BryanCutler/spark,actuaryzhang/spark,dhruve/spark,vinodkc/spark,aokolnychyi/spark,panfengfeng/spark,ddna1021/spark,srowen/spark,MLnick/spark,nchammas/spark,mike0sv/spark,Aegeaner/spark,HyukjinKwon/spark,tejasapatil/spark,facaiy/spark,joseph-torres/spark,chuckchen/spark,wangmiao1981/spark,esi-mineset/spark,stanzhai/spark,rezasafi/spark,loneknightpy/spark,kevinyu98/spark,panfengfeng/spark,tejasapatil/spark,publicRoman/spark,debugger87/spark,liyichao/spark,zzcclp/spark,xuanyuanking/spark,WeichenXu123/spark,zzcclp/spark,tengpeng/spark,mahak/spark,zero323/spark,zero323/spark,LantaoJin/spark,maropu/spark,shaneknapp/spark,byakuinss/spark,kimoonkim/spark,panfengfeng/spark,WeichenXu123/spark,ptkool/spark,xflin/spark,someorz/spark,SnappyDataInc/spark,rednaxelafx/apache-spark,saltstar/spark,stanzhai/spark,shaneknapp/spark,ajaysaini725/spark,andrewor14/spark,map222/spark,kissmetrics/spark,aray/spark,eyalfa/spark,kiszk/spark,tengpeng/spark,brad-kaiser/spark,shuangshuangwang/spark,zero323/spark,pgandhi999/spark,rednaxelafx/apache-spark,saltstar/spark,jlopezmalla/spark,ptkool/spark,zuotingbing/spark,jiangxb1987/spark,ioana-delaney/spark,minixalpha/spark,lxsmnv/spark,dongjoon-hyun/spark,maropu/spark,holdenk/spark,icexelloss/spark,andrewor14/spark,byakuinss/spark,apache/spark,cloud-fan/spark,rekhajoshm/spark,esi-mineset/spark,facaiy/spark,someorz/spark,apache/spark,xuanyuanking/spark,ajaysaini725/spark,nlalevee/spark,aosagie/spark,akopich/spark,holdenk/spark,techaddict/spark,zhouyejoe/spark,janewangfb/spark,wangyum/spark,ron8hu/spark,rikima/spark,hhbyyh/spark,dongjoon-hyun/spark,icexelloss/spark,kevinyu98/spark,mike0sv/spark,SnappyDataInc/spark,SHASHANKB/spark,jkbradley/spark,skonto/spark,gengliangwang/spark,aosagie/spark,sachintyagi22/spark,apache/spark,zuotingbing/spark,goldmedal/spark,facaiy/spark,SHASHANKB/spark,stanzhai/spark,HyukjinKwon/spark,michalsenkyr/spark,sachintyagi22/spark,byakuinss/spark,liyichao/spark,saturday-shi/spark,holdenk/spark,patrick-nicholson/spark,jianran/spark,setjet/spark,cin/spark,aray/spark,janewangfb/spark,dbtsai/spark,nlalevee/spark,lvdongr/spark,pgandhi999/spark,aokolnychyi/spark,someorz/spark,pgandhi999/spark,holdenk/spark,ddna1021/spark,MLnick/spark,wangmiao1981/spark,sureshthalamati/spark,saturday-shi/spark,nilsgrabbert/spark,setjet/spark,UndeadBaneGitHub/spark,panfengfeng/spark,techaddict/spark,jrshust/spark,tejasapatil/spark,michalsenkyr/spark,ddna1021/spark,alunarbeach/spark,cin/spark,byakuinss/spark,kissmetrics/spark,narahari92/spark,zhouyejoe/spark,ConeyLiu/spark,tengpeng/spark,UndeadBaneGitHub/spark,hvanhovell/spark,xflin/spark,adrian-ionescu/apache-spark,rednaxelafx/apache-spark,HyukjinKwon/spark,JoshRosen/spark,HyukjinKwon/spark,liutang123/spark,caneGuy/spark,shuangshuangwang/spark,hhbyyh/spark,metamx/spark,alunarbeach/spark,wangyum/spark,mdespriee/spark,alunarbeach/spark,lxsmnv/spark,jkbradley/spark,spark-test/spark,mahak/spark,eyalfa/spark,kissmetrics/spark,big-pegasus/spark,JerryLead/spark,BryanCutler/spark,esi-mineset/spark,kevinyu98/spark,wzhfy/spark,bOOm-X/spark,andrewor14/spark,skonto/spark,WeichenXu123/spark,saturday-shi/spark,rekhajoshm/spark,shuangshuangwang/spark,techaddict/spark,kissmetrics/spark,szhem/spark,JoshRosen/spark,kissmetrics/spark,BryanCutler/spark,sureshthalamati/spark,kiszk/spark,big-pegasus/spark,jrshust/spark,wangmiao1981/spark,poffuomo/spark,rikima/spark,ibm-research-ireland/sparkoscope,icexelloss/spark,esi-mineset/spark,eyalfa/spark,taroplus/spark,1haodian/spark,jkbradley/spark,saltstar/spark,xflin/spark,LantaoJin/spark,patrick-nicholson/spark,witgo/spark,setjet/spark,vinodkc/spark,alunarbeach/spark,SnappyDataInc/spark,markhamstra/spark,dhruve/spark,jlopezmalla/spark,jkbradley/spark,kevinyu98/spark,shubhamchopra/spark,bdrillard/spark,witgo/spark,dbtsai/spark,brad-kaiser/spark,xuanyuanking/spark,dhruve/spark,publicRoman/spark,sahilTakiar/spark,Aegeaner/spark,pgandhi999/spark,tengpeng/spark,ajaysaini725/spark,ConeyLiu/spark,dongjoon-hyun/spark,nilsgrabbert/spark,jiangxb1987/spark,apache-spark-on-k8s/spark,bdrillard/spark,shuangshuangwang/spark,joseph-torres/spark,srowen/spark,ibm-research-ireland/sparkoscope,icexelloss/spark,sahilTakiar/spark,darionyaphet/spark,zhouyejoe/spark,WindCanDie/spark,ConeyLiu/spark,apache/spark,1haodian/spark,jlopezmalla/spark