Fix compile errors

Change line 9779 from 
```ts
class QueryCollection<T> implements Array<T> {
```
to
```ts
class QueryCollection<T> extends Array<T> {
```
***Because I getting the error TS2420: Class 'QueryCollection<T>' incorrectly implements interface 'T[]'.***
***    Property 'find' is missing in type 'QueryCollection<T>'.***

After implementing find in .d.ts getting next error about method findIndex and so on.

Simplest way to fix it, was let QueryCollection  extends Array and not implement it.

***Typescript version***
1.8.7

winjs/winjs.d.ts

@@ -9774,7 +9774,7 @@ declare namespace WinJS.Utilities {
     /**
      * Represents the result of a query selector, and provides various operations that perform actions over the elements of the collection.
     **/
-    class QueryCollection<T> implements Array<T> {
+    class QueryCollection<T> extends Array<T> {
         //#region Methods
 
         /**