This updates the copyright header to all be the same, which is
pretty much an update of where to mail request for a copy of the GPL
and the years of the MPD project. This also puts all committers under
'The Music Player Project' umbrella. These entries should go
individually in the AUTHORS file, for consistancy.
This is a rather huge patch, which unfortunately cannot be splitted.
Instead of using our custom ioops.h library, convert everything to use
the GLib main loop.
