Ignore RPL_TOPICWHOTIME

We don't need this piece of information yet, and we don't want to
clutter the server buffer with channel messages.

components/app.js

@@ -404,6 +404,9 @@ export default class App extends Component {
 
 			this.setBufferState(channel, { topic });
 			break;
+		case irc.RPL_TOPICWHOTIME:
+			// Ignore
+			break;
 		case irc.RPL_NAMREPLY:
 			var channel = msg.params[2];
 			var membersList = msg.params[3].split(" ");