Added session usage docs. Closes #443
Added session usage docs. Closes #443

Ju2ender/express,awronka/express,philxia/ex-tst-framework,devgeniem/express,nodejs-camp/booklog-jason,nodejs-camp/booklog-leo,brianloveswords/express,abdulhannanali/express,isaacs/express,svnh/express,juandav/express,nodejs-camp/booklog-chenyou,supasate/express,Kevnz/express,sibura/express,nbeydoon/express,elkingtonmcb/express,leiqiang75/express,Faiz7412/express,maraoz/express,luxe-eng/valet-express.express,chrisinajar/express,LestaD/express,abhi3/express,Riokai/express,aifeld/express,micha149/express,gdeividas/express,smcmurray/express,vinodhalaharvi/express,mcanthony/express,nodejs-camp/booklog-homa,Riokai/express,dsupera13/express,smcmurray/express,saisai/express,HXYNODE/express,XueQian/express,simudream/express,soyuka/express,Talkyunyun/express,nodejs-camp/booklog-chle,chuym/express,1amageek/express,dongseop/express,devgeniem/express,corporateanon/express,qq645381995/express,evanlucas/express,1verson/express,jenalgit/express,leiqiang75/express,mimaidms/express,Riokai/express,lian774739140/express,jinghuizhai/express,abhi3/express,qitianchan/express,vinodhalaharvi/express,dotnetCarpenter/express,baldurh/express,kentcdodds/express,kylezhang/express,robomc/express,RickyDan/express,angelsanz/express,FernAbby/express,dafabulousteach/express,VegeChou/express,juanpastas/express,frootloops/express,demohi/express,ahdinosaur/express,fineday32/express,shanawarkhan/express,grigorkh/express,v10258/express,r14r-work/fork_express_master,mimaidms/express,hl198181/express,dreamingblackcat/express,Jonekee/express,kawanet/express,nodejs-camp/booklog-polo,BaggersIO/express,blainsmith/express,lemelon/express,r14r/fork_express_master,PUSEN/express,fuse-mars/express,junxiong/express,luxe-eng/valet-express.express,fuse-mars/express,simudream/express,topaxi/express,nodejs-camp/booklog-tonebeta-update,Lexine/express,nodejs-camp/booklog-archer,auth0/express,kunalpict/express,fakedarren/express,btleffler/express,vinodhalaharvi/express,thepont/express,vidyar/express,hpcslag/express,pathirana/express,udhayam/express,stevemao/express,TestingCI/express,frootloops/express,shanawarkhan/express,hdngr/express,maraoz/express,vidyar/express,isaacs/express,Kevnz/express,dgofman/express,Eric-Vandenberg/express,yinhe007/express,jimmykuo/express,codeforgeek/express,xiaofuzi/express,swarajgiri/express,benshiue/booklog-ben,pshomov/express,rupanjanbaidya/express,cflynn07/express,microlv/express,nodejs-camp/booklog-mora,andriyl/express,evilboss/express,Matrixbirds/express,stevemao/express,jenia0jenia/express,CrazySherman/express,swstack/express,FernAbby/express,flomotlik/express,mikewesthad/express,svnh/express,Ivanwangcy/express,Jonekee/express,WangCao/express,MoraLin/mora-test,stoskov/express,qq645381995/express,HXYNODE/express,tianhengzhou/express,v10258/express,wesleytodd/express,nbeydoon/express,nbeydoon/express,za-creature/express,dgofman/express,hacksparrow/express,adjohnson916/express,hacksparrow/express,ZackBotkin/express,nodejs-camp/booklog-s890506,hightechweb/express,PUSEN/express,hl198181/express,coreypnorris/express,rupanjanbaidya/express,drzorm/express,stewartml/express,caiocutrim/express,samuelcastro/express,nathan818fr/express,expressjs/express,saisai/express,dotnetCarpenter/express,wtony/express,ericlu88/express,strongloop/express,Flip120/express,jinghuizhai/express,blairzhang/express,nodejs-camp/booklog-jason,KodkodGates/express,TestingCI/express,fineday32/express,nodejs-camp/booklog-leo,bercanozcan/express,codeforgeek/express,thepont/express,jenia0jenia/express,ci-test2/express,heicx/express,methuz/express,nodejs-camp/booklog-ben,listepo/express,stoskov/express,WangCao/express,luxe-eng/valet-express.express,heicx/express,PeterWangPo/express,gdeividas/express,LestaD/express,nodejs-camp/booklog-chenyou,juandav/express,mcanthony/express,TestingCI/express,VegeChou/express,buildsample/express,ericlu88/express,za-creature/express,nodejs-camp/booklog-tonebeta-update,supasate/express,hdngr/express,michaeljunlove/express,Faiz7412/express,corporateanon/express,fanzetao/express,nodejs-camp/booklog-Zak,Eric-Vandenberg/express,featurist/express,neomadara/express,1verson/express,demohi/express,Haru1990/express,dieuly/express,ifraixedes/express,blakeembrey/express,pstrike/express,YR/express,jimmykuo/express,nodejs-camp/booklog-linkchen,igarciaes/express,buildsample/express,sarvex/express,Faiz7412/express,maraoz/express,Talkyunyun/express,za-creature/express,buildsample/express,danielrohers/express,blairzhang/express,evilboss/express,Haru1990/express,nodejs-camp/booklog-tonebeta,ahdinosaur/express,jenia0jenia/express,kentcdodds/express,adjohnson916/express,stewartml/express,BaggersIO/express,ZackBotkin/express,bjrmatos/express,nodejs-camp/booklog-ben,weilixia/express,vnglst/express,micha149/express,Lexine/express,ZackBotkin/express,Eric-Vandenberg/express,hanweifish/express,blakeembrey/express,philxia/ex-tst-framework,nodejs-camp/booklog-Zak,WangCao/express,listepo/express,chrisinajar/express,pstrike/express,blairzhang/express,nathan818fr/express,jymsy/express,coreypnorris/express,wtony/express,abdulhannanali/express,dongseop/express,llwanghong/express,lmtdit/express,r14r-work/fork_express_master,auth0/express,abdulhannanali/express,emvici/emvici-reqres-tify,qitianchan/express,jymsy/express,youprofit/express,vnglst/express,friederbluemle/express,1amageek/express,philxia/ex-tst-framework,robomc/express,JulyZhu/express,nodejs-camp/booklog-s890506,xiaofuzi/express,r14r/fork_express_master,grigorkh/express,nodejs-camp/booklog-homa,RanadeepPolavarapu/express,bjrmatos/express,igarciaes/express,neomadara/express,MoraLin/mora-test,stevemao/express,dsupera13/express,wesleytodd/express,tjmehta/express,chuym/express,ralic/express,weilixia/express,nodejs-camp/booklog-ausir,kunalpict/express,mauricionr/express,dafabulousteach/express,dreamingblackcat/express,abhi3/express,smcmurray/express,kubrickology/express,mauricionr/express,nodejs-camp/booklog-mora,nodejs-camp/booklog-jollen,sujianping/express,awronka/express,LestaD/express,simplyianm/express,topaxi/express,caiocutrim/express,countdracular/express,ci-test2/express,gnowoel/express,tyler-johnson/express,mikewesthad/express,1amageek/express,hanqingnan/express,benshiue/booklog-ben,sarvex/express,samuelcastro/express,lmtdit/express,swstack/express,andrejewski/express,coreypnorris/express,topaxi/express,soyuka/express,dongooo/express,nodejs-camp/booklog-linkchen,nodejs-camp/booklog-jollen,bercanozcan/express,dafabulousteach/express,countdracular/express,juanpastas/express,grigorkh/express,swarajgiri/express,xiaofuzi/express,jenalgit/express,jenalgit/express,nodejs-camp/booklog-archer,wtony/express,kubrickology/express,danielrohers/express,xtidt/express,chrisinajar/express,svnh/express,simplyianm/express,rgrove/express,pathirana/express,XueQian/express,friederbluemle/express,stoskov/express,KodkodGates/express,sibura/express,nodejs-camp/booklog-ansaga,Ivanwangcy/express,nodejs-camp/booklog-polo,expressjs/express,gnowoel/express,fakedarren/express,tyler-johnson/express,Flip120/express,nodejs-camp/booklog-polo,nodejs-camp/booklog-tonebeta,hanqingnan/express,kunalpict/express,stewartml/express,featurist/express,evanlucas/express,gretac/express,BaggersIO/express,vidyar/express,hpcslag/express,kylezhang/express,andrejewski/express,dieuly/express,YR/express,cflynn07/express,blakeembrey/express,featurist/express,qitianchan/express,hightechweb/express,junxiong/express,bercanozcan/express,friederbluemle/express,KodkodGates/express,dongooo/express,strongloop/express,lian774739140/express,sujianping/express,WebStyle/express,PeterWangPo/express,philxia/ex-tst-framework,christopheranderson/express,srichatala/express,hanweifish/express,WebStyle/express,youprofit/express,kylezhang/express,listepo/express,junxiong/express,lemelon/express,btleffler/express,blainsmith/express,CrazySherman/express,lmtdit/express,microlv/express,corporateanon/express,vnglst/express,michaeljunlove/express,tfe/express,udhayam/express,andriyl/express,elkingtonmcb/express,XueQian/express,swarajgiri/express,gretac/express,nodejs-camp/booklog-ausir,RickyDan/express,simudream/express,michaeljunlove/express,angelsanz/express,ci-test2/express,yinhe007/express,drzorm/express,flomotlik/express,supasate/express,gnowoel/express,nodejs-camp/booklog-ansaga,tianhengzhou/express,qq645381995/express,Ju2ender/express,xtidt/express,nodejs-camp/booklog-chle,baldurh/express,hpcslag/express,v10258/express,dreamingblackcat/express,methuz/express,devgeniem/express,jinghuizhai/express,pshomov/express,ralic/express,dongseop/express,Matrixbirds/express,JulyZhu/express,tjmehta/express,fanzetao/express,RanadeepPolavarapu/express,angelsanz/express,fakedarren/express,evilboss/express,srichatala/express,hdngr/express,ifraixedes/express,christopheranderson/express,kawanet/express,rgrove/express,Flip120/express,Ju2ender/express,sarvex/express,dotnetCarpenter/express,llwanghong/express,youprofit/express,aifeld/express