multi: fixes for timing out handles

Add a timeout check for handles in the state machine so that they will
timeout in all states disregarding what actions that may or may not
happen.

Fixed a bug in socket_action introduced recently when looping over timed
out handles: it wouldn't assign the 'data' variable and thus it wouldn't
properly take care of handles.

In the update_timer function, the code now checks if the timeout has
been removed and then it tells the application. Previously it would
always let the remaining timeout(s) just linger to expire later on.