Merge pull request #1245 from borisyankov/momentjs-zone-function

Momentjs zone function

moment/moment.d.ts

@@ -121,6 +121,8 @@ interface Moment {
 
     isLeapYear(): boolean;
     zone(): number;
+    zone(b: number): Moment;
+    zone(b: string): Moment;
     daysInMonth(): number;
     isDST(): boolean;