Adds requests library to setup's required libraries.
Adds requests library to setup's required libraries.

So that loading of external data works 'out of the box'.

gwulfs/zipline,ronalcc/zipline,chrjxj/zipline,DVegaCapital/zipline,CarterBain/AlephNull,dkushner/zipline,erikness/AlephOne,zhoulingjun/zipline,zhoulingjun/zipline,euri10/zipline,morrisonwudi/zipline,grundgruen/zipline,michaeljohnbennett/zipline,kmather73/zipline,humdings/zipline,grundgruen/zipline,CDSFinance/zipline,iamkingmaker/zipline,StratsOn/zipline,Scapogo/zipline,stkubr/zipline,YuepengGuo/zipline,AlirezaShahabi/zipline,wilsonkichoi/zipline,CarterBain/AlephNull,nborggren/zipline,umuzungu/zipline,kmather73/zipline,dhruvparamhans/zipline,keir-rex/zipline,alphaBenj/zipline,aajtodd/zipline,CDSFinance/zipline,enigmampc/catalyst,cmorgan/zipline,jimgoo/zipline-fork,YuepengGuo/zipline,iamkingmaker/zipline,davidastephens/zipline,DVegaCapital/zipline,MonoCloud/zipline,florentchandelier/zipline,umuzungu/zipline,humdings/zipline,cmorgan/zipline,bartosh/zipline,stkubr/zipline,wubr2000/zipline,nborggren/zipline,dhruvparamhans/zipline,semio/zipline,ChinaQuants/zipline,semio/zipline,euri10/zipline,otmaneJai/Zipline,sketchytechky/zipline,erikness/AlephOne,morrisonwudi/zipline,keir-rex/zipline,mattcaldwell/zipline,jordancheah/zipline,jimgoo/zipline-fork,otmaneJai/Zipline,davidastephens/zipline,ChinaQuants/zipline,chrjxj/zipline,dmitriz/zipline,quantopian/zipline,florentchandelier/zipline,dkushner/zipline,StratsOn/zipline,magne-max/zipline-ja,ronalcc/zipline,bartosh/zipline,wilsonkichoi/zipline,enigmampc/catalyst,joequant/zipline,joequant/zipline,alphaBenj/zipline,jordancheah/zipline,Scapogo/zipline,MonoCloud/zipline,AlirezaShahabi/zipline,sketchytechky/zipline,wubr2000/zipline,michaeljohnbennett/zipline,gwulfs/zipline,magne-max/zipline-ja,mattcaldwell/zipline,quantopian/zipline,dmitriz/zipline,aajtodd/zipline