Just show 'Call' for call events. Don't just splat out the content of the...

Just show 'Call' for call events. Don't just splat out the content of the event for other events: it's rarely going to be sesnible.

webclient/recents/recents.html

@@ -51,7 +51,9 @@
                         </div>
 
                         <div ng-switch-default>
-                            {{ room.lastMsg }}
+                            <div ng-if="room.lastMsg.type.indexOf('m.call.') == 0">
+                                Call
+                            </div>
                         </div>
                     </div>
                 </td>