always return an array of payloads

Author: robrichard

src/fetch.js

@@ -41,7 +41,7 @@ export function fetchImpl(
                 });
             } else {
                 return response.json().then(json => {
-                    onNext(json);
+                    onNext([json]);
                     onComplete();
                 });
             }

src/xhr.js

@@ -41,7 +41,7 @@ export function xhrImpl(
             patchResolver.handleChunk(chunk);
             index = xhr.responseText.length;
         } else if (this.readyState === this.DONE && !isDeferred) {
-            onNext(JSON.parse(xhr.response));
+            onNext([JSON.parse(xhr.response)]);
             onComplete();
         }
     }