fix(repeat): add additional resubscription behavior
fix(repeat): add additional resubscription behavior

- repeat operator now supports resubscription behavior properly along
with infinite repeat

closes #516

kwonoj/RxJS,adrianomelo/RxJSNext,Brocco/RxJS,martinsik/rxjs,Igorbek/rxjs5,robwormald/RxJS,adrianomelo/RxJS-1,SangKa/RxJS-Docs-CN,SangKa/RxJS-Docs-CN,kwonoj/RxJS,mattpodwysocki/RxJS,martinsik/rxjs,figueredo/RxJS,benlesh/RxJS,adrianomelo/RxJS-1,mattpodwysocki/RxJS,adrianomelo/RxJSNext,IgorMinar/RxJS,jayphelps/rxjs,SangKa/RxJS-Docs-CN,jayphelps/rxjs,ReactiveX/RxJS,benlesh/RxJS,figueredo/RxJS,staltz/RxJSNext,jayphelps/rxjs,jayphelps/rxjs,elliotschi/rxjs,gluck/RxJS,robwormald/RxJS,IgorMinar/RxJS,jinroh/RxJS,elliotschi/rxjs,robwormald/RxJS,saneyuki/RxJS,trxcllnt/RxJS,jadbox/RxJS,RxJS-CN/RxJS-Docs-CN,kwonoj/RxJS,figueredo/RxJS,staltz/RxJSNext,RxJS-CN/RxJS-Docs-CN,elliotschi/rxjs,jinroh/RxJS,trxcllnt/RxJS,ReactiveX/rxjs,martinsik/rxjs,ReactiveX/rxjs,ReactiveX/rxjs,adrianomelo/RxJS-1,Igorbek/rxjs5,jadbox/RxJS,jadbox/RxJS,gluck/RxJS,adrianomelo/RxJSNext,justinwoo/RxJS,gluck/RxJS,adrianomelo/RxJSNext,justinwoo/RxJS,trxcllnt/RxJS,robwormald/RxJS,benlesh/RxJS,justinwoo/RxJS,Brocco/RxJS,Igorbek/rxjs5,jinroh/RxJS,mattpodwysocki/RxJS,adrianomelo/RxJS-1,kwonoj/RxJS,ReactiveX/RxJS,saneyuki/RxJS,SangKa/RxJS-Docs-CN,ReactiveX/RxJS,ReactiveX/RxJS,elliotschi/rxjs,RxJS-CN/RxJS-Docs-CN,staltz/RxJSNext,mattpodwysocki/RxJS,Brocco/RxJS,trxcllnt/RxJS,jadbox/RxJS,figueredo/RxJS,ReactiveX/rxjs,RxJS-CN/RxJS-Docs-CN,jinroh/RxJS,jayphelps/rxjs,Igorbek/rxjs5,Brocco/RxJS,martinsik/rxjs,justinwoo/RxJS,staltz/RxJSNext,benlesh/RxJS,gluck/RxJS