Needs methods as well

I am in need to extend the component after its being used with the `connect()`. The extended component was missing with `methods`. So here is the possible fix.

Author: itsazzad

src/connect.js

@@ -113,7 +113,9 @@ export default function connect(mapStateToProps, mapActionsToProps) {
 
       beforeDestroy() {
         this.vuaReduxUnsubscribe();
-      }
+      },
+
+      methods: children.methods
     };
   };
 }