- Add flag to indicate when main loop has ended.

- Add flag to indicate when main loop has ended.
- Don't allow (some) events during shutdown, as events wont be processed.
- Don't remove drop handlers on dnd shutdown, they should be removed by
  their creators.
- init/shutdown fwin
- Delete fwins on shutdown.
- Remove weird ipc wrapper function.
- Don't do additional shutdown functions on restart.

SVN revision: 29366