Added req.header() tests
Added req.header() tests

ZackBotkin/express,Ju2ender/express,cflynn07/express,corporateanon/express,tyler-johnson/express,pshomov/express,isaacs/express,ralic/express,Kevnz/express,fineday32/express,kylezhang/express,andrejewski/express,wtony/express,maraoz/express,hdngr/express,listepo/express,leiqiang75/express,dreamingblackcat/express,sarvex/express,juandav/express,swarajgiri/express,JulyZhu/express,nodejs-camp/booklog-jollen,stewartml/express,hacksparrow/express,nodejs-camp/booklog-ben,KodkodGates/express,abdulhannanali/express,nodejs-camp/booklog-jollen,bercanozcan/express,jinghuizhai/express,xiaofuzi/express,fuse-mars/express,saisai/express,ericlu88/express,kunalpict/express,BaggersIO/express,soyuka/express,RanadeepPolavarapu/express,stewartml/express,kubrickology/express,wtony/express,kawanet/express,coreypnorris/express,KodkodGates/express,nodejs-camp/booklog-leo,Flip120/express,mcanthony/express,xtidt/express,micha149/express,nodejs-camp/booklog-ansaga,LestaD/express,samuelcastro/express,evilboss/express,andriyl/express,kylezhang/express,udhayam/express,Haru1990/express,kentcdodds/express,hanweifish/express,bercanozcan/express,corporateanon/express,llwanghong/express,pshomov/express,stoskov/express,fakedarren/express,abdulhannanali/express,codeforgeek/express,ahdinosaur/express,nodejs-camp/booklog-chenyou,xtidt/express,qitianchan/express,lmtdit/express,strongloop/express,qitianchan/express,coreypnorris/express,mauricionr/express,YR/express,saisai/express,featurist/express,mcanthony/express,youprofit/express,Ivanwangcy/express,FernAbby/express,Kevnz/express,Eric-Vandenberg/express,mimaidms/express,MoraLin/mora-test,luxe-eng/valet-express.express,HXYNODE/express,frank06/express,auth0/express,LestaD/express,Riokai/express,abdulhannanali/express,sibura/express,christopheranderson/express,abhi3/express,btleffler/express,vnglst/express,YR/express,baldurh/express,MoraLin/mora-test,dongseop/express,fineday32/express,vidyar/express,hdngr/express,supasate/express,hdngr/express,KodkodGates/express,1amageek/express,luxe-eng/valet-express.express,nathan818fr/express,wesleytodd/express,stewartml/express,dsupera13/express,youprofit/express,dsupera13/express,smcmurray/express,nodejs-camp/booklog-linkchen,jimmykuo/express,evilboss/express,za-creature/express,jinghuizhai/express,FernAbby/express,youprofit/express,buildsample/express,wtony/express,fakedarren/express,methuz/express,benshiue/booklog-ben,sarvex/express,nodejs-camp/booklog-mora,TestingCI/express,qitianchan/express,dgofman/express,svnh/express,srichatala/express,hanweifish/express,Jonekee/express,angelsanz/express,tjmehta/express,codeforgeek/express,nodejs-camp/booklog-polo,juanpastas/express,weilixia/express,danielrohers/express,mimaidms/express,junxiong/express,lemelon/express,qq645381995/express,ci-test2/express,Riokai/express,shanawarkhan/express,xiaofuzi/express,kentcdodds/express,frank06/express,swarajgiri/express,Faiz7412/express,Riokai/express,LestaD/express,baldurh/express,nathan818fr/express,gnowoel/express,elkingtonmcb/express,gretac/express,isaacs/express,yinhe007/express,r14r-work/fork_express_master,jenia0jenia/express,hightechweb/express,svnh/express,blairzhang/express,stevemao/express,vinodhalaharvi/express,nodejs-camp/booklog-Zak,blairzhang/express,heicx/express,kawanet/express,philxia/ex-tst-framework,hightechweb/express,bercanozcan/express,stevemao/express,igarciaes/express,nodejs-camp/booklog-polo,nodejs-camp/booklog-jason,blakeembrey/express,nodejs-camp/booklog-tonebeta,awronka/express,Ju2ender/express,chuym/express,caiocutrim/express,TestingCI/express,jenalgit/express,listepo/express,expressjs/express,WebStyle/express,frootloops/express,buildsample/express,tyler-johnson/express,chrisinajar/express,blakeembrey/express,nodejs-camp/booklog-archer,chrisinajar/express,lian774739140/express,sibura/express,jimmykuo/express,ci-test2/express,stoskov/express,dongooo/express,dreamingblackcat/express,nodejs-camp/booklog-Zak,junxiong/express,pstrike/express,adjohnson916/express,fuse-mars/express,nodejs-camp/booklog-jason,christopheranderson/express,nbeydoon/express,aifeld/express,hl198181/express,1amageek/express,ifraixedes/express,kunalpict/express,vidyar/express,expressjs/express,luxe-eng/valet-express.express,Eric-Vandenberg/express,nodejs-camp/booklog-chenyou,udhayam/express,RickyDan/express,corporateanon/express,andrejewski/express,BaggersIO/express,hanqingnan/express,llwanghong/express,qq645381995/express,hpcslag/express,wesleytodd/express,PUSEN/express,friederbluemle/express,nodejs-camp/booklog-tonebeta,devgeniem/express,neomadara/express,demohi/express,rupanjanbaidya/express,tfe/express,nodejs-camp/booklog-tonebeta-update,ZackBotkin/express,srichatala/express,cflynn07/express,v10258/express,evanlucas/express,dieuly/express,juanpastas/express,hl198181/express,Matrixbirds/express,nodejs-camp/booklog-homa,vnglst/express,simudream/express,vinodhalaharvi/express,drzorm/express,flomotlik/express,michaeljunlove/express,neomadara/express,v10258/express,kubrickology/express,btleffler/express,ericlu88/express,CrazySherman/express,1amageek/express,listepo/express,r14r-work/fork_express_master,gretac/express,Faiz7412/express,mikewesthad/express,vinodhalaharvi/express,dongooo/express,lian774739140/express,RickyDan/express,aifeld/express,WangCao/express,nbeydoon/express,Eric-Vandenberg/express,philxia/ex-tst-framework,Flip120/express,ahdinosaur/express,za-creature/express,dotnetCarpenter/express,nodejs-camp/booklog-ansaga,nbeydoon/express,devgeniem/express,robomc/express,gnowoel/express,friederbluemle/express,nodejs-camp/booklog-ben,pathirana/express,simudream/express,weilixia/express,pstrike/express,stevemao/express,grigorkh/express,za-creature/express,Faiz7412/express,rupanjanbaidya/express,friederbluemle/express,rgrove/express,sujianping/express,microlv/express,evilboss/express,sarvex/express,swarajgiri/express,RanadeepPolavarapu/express,jymsy/express,fanzetao/express,1verson/express,blainsmith/express,qq645381995/express,nodejs-camp/booklog-ausir,smcmurray/express,Jonekee/express,nodejs-camp/booklog-mora,nodejs-camp/booklog-chle,blainsmith/express,dafabulousteach/express,elkingtonmcb/express,rgrove/express,HXYNODE/express,dotnetCarpenter/express,flomotlik/express,topaxi/express,awronka/express,shanawarkhan/express,michaeljunlove/express,hacksparrow/express,JulyZhu/express,bjrmatos/express,gnowoel/express,nodejs-camp/booklog-chle,TestingCI/express,VegeChou/express,supasate/express,nodejs-camp/booklog-polo,topaxi/express,thepont/express,ci-test2/express,devgeniem/express,ZackBotkin/express,thepont/express,gdeividas/express,dafabulousteach/express,hpcslag/express,coreypnorris/express,nodejs-camp/booklog-archer,philxia/ex-tst-framework,nodejs-camp/booklog-homa,philxia/ex-tst-framework,adjohnson916/express,mikewesthad/express,topaxi/express,drzorm/express,supasate/express,grigorkh/express,jinghuizhai/express,abhi3/express,fakedarren/express,leiqiang75/express,heicx/express,Matrixbirds/express,nodejs-camp/booklog-tonebeta-update,hpcslag/express,Ju2ender/express,featurist/express,robomc/express,dgofman/express,VegeChou/express,smcmurray/express,dreamingblackcat/express,chuym/express,svnh/express,jenalgit/express,angelsanz/express,grigorkh/express,simudream/express,WangCao/express,junxiong/express,gdeividas/express,r14r/fork_express_master,xiaofuzi/express,swstack/express,nodejs-camp/booklog-ausir,jymsy/express,strongloop/express,jenalgit/express,chrisinajar/express,Talkyunyun/express,angelsanz/express,Ivanwangcy/express,Lexine/express,CrazySherman/express,micha149/express,lmtdit/express,brianloveswords/express,dongseop/express,evanlucas/express,Talkyunyun/express,stoskov/express,kylezhang/express,yinhe007/express,XueQian/express,methuz/express,tianhengzhou/express,WangCao/express,simplyianm/express,pathirana/express,ifraixedes/express,ralic/express,PeterWangPo/express,fanzetao/express,Flip120/express,maraoz/express,kunalpict/express,caiocutrim/express,vidyar/express,PeterWangPo/express,nodejs-camp/booklog-linkchen,tjmehta/express,dieuly/express,buildsample/express,andriyl/express,r14r/fork_express_master,demohi/express,simplyianm/express,auth0/express,tianhengzhou/express,v10258/express,WebStyle/express,PUSEN/express,XueQian/express,maraoz/express,blairzhang/express,samuelcastro/express,BaggersIO/express,mauricionr/express,microlv/express,sujianping/express,emvici/emvici-reqres-tify,frootloops/express,jenia0jenia/express,Haru1990/express,swstack/express,soyuka/express,nodejs-camp/booklog-s890506,hanqingnan/express,countdracular/express,countdracular/express,jenia0jenia/express,benshiue/booklog-ben,Lexine/express,blakeembrey/express,XueQian/express,igarciaes/express,dongseop/express,juandav/express,lemelon/express,michaeljunlove/express,vnglst/express,danielrohers/express,lmtdit/express,1verson/express,featurist/express,dotnetCarpenter/express,bjrmatos/express,dafabulousteach/express,nodejs-camp/booklog-leo,nodejs-camp/booklog-s890506,abhi3/express