Fixed a bug where controlbox wasn't available on xmppchat.chatboxesview, instead pass the removal of the model to rosterview.model
Changed the following:
- Subscribe event with help of jQuery one instead of delegate, now that
  the rosterView is no longer emptied on every render to avoid
  registring several handlers of remove action, which meant you had to
  click 4 times for the jQuery Dialog to go away
- Remove the element from the rosterView when the remove event is
  triggered on the model which removes just that item instead of
  emptying the list and appending the remaining models again