Show users editing and lag, properly send message to indicate that all users have left channel and show basic error box if disconnected.

bower.json

@@ -21,6 +21,7 @@
     "jquery": "~2.1.1",
     "tweetnacl": "~0.12.2",
     "ckeditor": "~4.4.5",
-    "requirejs": "~2.1.15"
+    "requirejs": "~2.1.15",
+    "modalBox": "~1.0.2"
   }
 }