[Rx.Observable.prototype.mergeAll(),

Rx.Observable.prototype.mergeObservable() ](https://github.com/Reactive-Extensions/RxJS/blob/master/src/core/linq/observable/mergeall.js)

Merges an observable sequence of observable sequences into an observable sequence.

返回值

(Observable): The observable sequence that merges the elements of the inner sequences.

例