add sendMessageWithNoRefresh and have broadcastMessage use it

This patch:
- moves broadcastMessage and restart from Core to Operations (to avoid
  circular imports);
- in Operations introduces sendMessageWithNoRefresh and move
 updateLayout outside windows.
- broadcastMessage now uses sendMessageWithNoRefresh to obey to this
  rules:
  1. if handleMessage returns Nothing no action is taken;
  2. if handleMessage returns a Just ml *only* the layout field of the
     workspace record will be updated.

darcs-hash:20080223130702-32816-60d71cd8ac32cff1d4039947142332023274a725

0 files changed, 0 insertions, 0 deletions