Basic support for Direct Stream Digital.  No conversion yet, and no
decoder/output plugin support.

Resets the libsamplerate state.  Not being used yet.

(Maybe it should be "A new message is indicated...", I don't know.)
(                                ^^                               )

This might break older versions, I didn't test.

The main difference is that strncat takes the maximum number of
characters to copy as its third argument, while g_strlcat takes
the size of the buffer, which is how the code was using strncat.

Incomplete requests may still be constructed as a result of the
reqest buffer filling up.

size_t is unsigned most of the time, so we can't really use it to
check for negative values. Also handle strtol overflow.

An empty string is obviously not a valid integer.

Shortcut for map_directory_fs(db_get_root()).

Work around a confusing error message.

Avoid reversing the order after every update.

Conflicts:
	NEWS
	configure.ac
	src/decoder/ffmpeg_decoder_plugin.c
	test/read_tags.c

This was disabled when compiled with a new ffmpeg version.  Older
ffmpeg versions used it explicitly, while newer ones may pass it
through from the codec.

This fixes seeking in the vorbis decoder during MPD startup.