Prepare to fix loading arbitrary song files from stored playlists.

Fixes busy loop when USB sound device gets unplugged (Mantis bug
#3824).

Player_LoadTitle() returns an aligned pointer in libmikmod-3.2 that
cannot be freed with free(). The correct way to do this now is
MikMod_free() which extracts the original pointer from the buffer and
frees that.
Signed-off-by: Christoph Mende <mende.christoph@gmail.com>

Fixes Mantis #3770.

there are some places in the mpd-0.17.4 sources where a "false" is
used instead of a NULL pointer.

mpd.conf.5 lists follow_outside_symlinks and follow_inside_symlinks
under REQUIRED, yet also documents a default value for these options,
which only makes sense if they're not actually required.

Fixes valgrind warning.

Eliminates one IDLE_PLAYER call in playlist_control, and add two new
ones to player_thread.  Fixes Mantis bug 3636.

Check audio_format_defined().

AVFrame must be allocated with avcodec_alloc_frame().

If END is omitted, mpd should use the highest possible value instead of raising an error.
This partially reverts 52e9cab1

When all outputs fail, MPD automatically pauses playback, but did not
emit the IDLE_PLAYER event.  Thus, clients were not woken up.  (Mantis
3665)

This file is generated during configuration and should be ignored.

- Add mandatory "name" setting for winmm/openal examples.

- Fix the language in openal sample (a -> an)

- Added replaygain_missing_preamp and replaygain_limit settings

- Added information about "auto" replay gain mode

At least in my configuration libgme lacks .pc file
thus could not be detected with pkg-config.