docs(do): add inline docs for do
docs(do): add inline docs for do

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