Add an option for each audio output which enables the use of the
hardware mixer, instead of the software volume code.

This is hardware specific, and assumes linear volume control.  This is
not the case for hardware mixers which were tested, making this patch
somewhat useless, but we will use it to experiment with the settings,
to find a good solution.

Apply the replay gain in the output thread.  This means a new setting
will be active instantly, without going through the whole music pipe.
And we might have different replay gain settings for each audio output
device.

Don't allocate each replay_gain_info object on the heap.  Those
objects who held a pointer now store a full replay_gain_info object.
This reduces the number of allocations and heap fragmentation.

The previous patch not only moved code, it also changed the check.
Negative gain values seem to be valid after all, there just was the
"magic" value 0.0 which means "not available".  This patch changes the
"magic" value to "INFINITY", and uses the C99 function isinf() to
check.  It might have been a better idea to use "NAN", but the "NAN"
macro is a GNU extension.

Moved (and renamed) the function calc_replay_gain_scale() to
replay_gain_info.c.

This function determines whether replay gain data is available.

This document has been unmaintained for more than a year now (since
the day it was submitted).

Same for "listplaylistinfo".

The only "return" statement always returns 0.

Use MPD_AUTO_RESULT().  Don't force libwrap by default.

Pass the current URI to wavpack_open_wvc().

Don't use the function ffmpeg_helper(), don't initialize the codec.

Fix a memory leak in some code paths.

Use input_stream.uri.

All close() implementations must call this method.

Conflicts:
	Makefile.am
	NEWS
	configure.ac
	src/decoder/ffmpeg_decoder_plugin.c
	src/decoder_thread.c

When all plugins have failed, MPD used to fall back to the "mad"
decoder plugin, to handle those radio streams without a Content-Type
response header.  This however leads to unexpected results (garbage
being played) when the stream isn't really mp3.  Since we care little
about "bad" streams, we shouldn't have hacks which have bad side
effects.

Let's get rid of this hack now!  Only try to "mad" plugin if there was
no match at all (Content-Type, path suffix) and no other plugin has
been tried.

Manage a linked list of plugins which were already tried.

Taken from the ffmpeg sources.

Use the correct parameter name.

Only delete the newline characters (\n and optionally \r).  This
allows the database file to store file names with trailing whitespace.

When enabling the pulse device fails, clear po->mainloop after
pa_threaded_mainloop_free() has finished.  This is important for the
assertions.

Two wrong g_free() calls were also removed.

Needed for the fluidsynth decoder plugin.

To allow libavformat to detect the format of the input file, append
the suffix of the input file to the URL of the virtual stream.  This
specifically enables the "shorten" codec, which is supported by
libavformat/raw.c, detected only by the suffix.

Allow declaration after statement.