Since we switched from autotools to Meson in commit
94592c14, we don't need to include
`config.h` early to properly enable large file support.  Meson passes
the required macros on the compiler command line instead of defining
them in `config.h`.

This means we can include `config.h` at any time, whenever we want to
check its macros, and there are no ordering constraints.

All DetachedSong instances should be converted to LightSong first,
which is a very cheap operation.

This code (added 7 years ago with commit b233c145) has been obsoleted
by the SongLoader class (added 3 years ago).

Works around a build failure on Solaris because annoyingly, Solaris
reserves the name "queue".  This rename was pending anyway.

From now on, struct Song will be used by the database only, and
DetachedSong will be used by everybody else.  DetachedSong is easier
to use, but Song has lower overhead.

Merge locate_song_search() and locate_song_match().

Fold the case during construction, without having to create another
copy.

Sorts remaining songs by priority.  This can be used for the
much-demanded "queue feature".

If a song with an absolute path points inside the music directory,
print only the relative part.  This happens when partial songs from a
playlist file were loaded.

I've already changed the "playlistinfo" command to hide HTTP
passwords, but forgot to do the same for the simpler "playlist"
command.  This patch changes queue_print_uris() to use the code from
song_print_uri().

After we've been hit by Large File Support problems several times in
the past week (which only occur on 32 bit platforms, which I don't
have), this is yet another attempt to fix the issue.

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.

Merged casefolding code from two locations into this one library
function.

Changed the function prototypes to get locate_item_list objects
instead of num_items/items.