[SPARK-18145] Update documentation for hive partition management in 2.1
[SPARK-18145] Update documentation for hive partition management in 2.1

## What changes were proposed in this pull request?

This documents the partition handling changes for Spark 2.1 and how to migrate existing tables.

## How was this patch tested?

Built docs locally.

rxin

Author: Eric Liang <ekl@databricks.com>

Closes #16074 from ericl/spark-18145.

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