Add multiple arguments support again

Suggested in issue #51 by huhk-sysu and partially fixed in PR #52.
This commit allow multiple arguments for message handlers without
the use of a store.

src/Observer.js

@@ -22,7 +22,7 @@ export default class{
         this.Socket.onevent = (packet) => {
             super_onevent.call(this.Socket, packet);
 
-            Emitter.emit(packet.data[0], packet.data[1]);
+            Emitter.emit( ...packet.data);
 
             if(this.store) this.passToStore('SOCKET_'+packet.data[0],  [ ...packet.data.slice(1)])
         };