chore(documentation): Update share documentation
chore(documentation): Update share documentation

Improve documenation on how .share() is different from .publish().refCount().

benlesh/RxJS,Brocco/RxJS,benlesh/RxJS,jayphelps/rxjs,trxcllnt/RxJS,trxcllnt/RxJS,ReactiveX/RxJS,kwonoj/RxJS,martinsik/rxjs,Brocco/RxJS,jayphelps/rxjs,Brocco/RxJS,martinsik/rxjs,martinsik/rxjs,martinsik/rxjs,IgorMinar/RxJS,ReactiveX/rxjs,benlesh/RxJS,kwonoj/RxJS,jayphelps/rxjs,trxcllnt/RxJS,ReactiveX/rxjs,ReactiveX/RxJS,ReactiveX/rxjs,IgorMinar/RxJS,kwonoj/RxJS,jayphelps/rxjs,Brocco/RxJS,kwonoj/RxJS,jayphelps/rxjs,benlesh/RxJS,ReactiveX/rxjs,trxcllnt/RxJS,ReactiveX/RxJS,ReactiveX/RxJS