broadcasts each tried closing of an object to all interest listener
The called object for closing must post the closing events immediately
and before any internal cancel operations will be started.
If a listener disagree with that it should throw a CloseVetoException
and called function XCloseable::close must be breaked immediately.
It's not allowed to catch it inside the close() request.
If no listener nor internal processes hinder the object on closing
all listener get's a notification about real closing.
