Add notification to group chat rooms with ongoing conf calls

This notification disappears when in the conf call / when the call is over.
CSS stolen from the desktop notification bar.

src/controllers/organisms/RoomList.js

@@ -112,7 +112,7 @@ module.exports = {
                             return m.userId !== member.userId
                         })[0];
                         if (ConferenceHandler.isConferenceUser(otherMember)) {
-                            console.log("Hiding conference 1:1 room %s", room.roomId);
+                            // console.log("Hiding conference 1:1 room %s", room.roomId);
                             shouldShowRoom = false;
                         }
                     }