Adds quarter date utilities back into zipline.
Adds quarter date utilities back into zipline.

Paving the way for a refactoring that will bring some of the
universe logic, specifically quarter universe logic into zipline.

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