Make sure we remove the callback before quitting

* add the new icons by Simon Damkjaer Anderson <simondamkjaer@gmail.com>, so Trax doesn't need to bootstrap over and over again. Implementation follows later on

* don't add -Wall to the obj-C flags, as you'll get flooded with useless warnings and don't see the errors anymore

Fix a debug message

This will help reduce useless process wakeups

* Don't find playlist
* Fix a few bugs in notification plugins

Todo: find a way to get rid of this mostly redundant code and rewrite the XOSD plugin

Don't remove AC_PROG_CPP our headerfile and library checking macros depend on it. Unbreak configure.ac

* various improvements to our Apple Remote bindings by the original author of the inofficial API, Martin Kahr (martin at his surname.com)

I'm far from being sure this is the right thing to do, but it allows MMSH to work correctly (it requests some data while the server is closing connection)

Do not search for playlist