Fix distcheck.

Adds mixrampdb and mixrampdelay commands.  Reads MIXRAP_START and
MIXRAMP_END tags from FLAC files and overlaps instead of crossfading.

For int16_t.

When decoder->timestamp is calculated, the PCM data is already
converted to out_audio_format; using in_audio_format may cause funny
speedups/slowdowns.

When handle_update() was modified to use uri_safe_local(), suddently
"mpc update ''" and "mpc update '/'" stopped working, because both are
not a "safe" local URI.  This patch adds a special case for these, to
retain backwards compatibility.

Did you ever accidently click "stop" while feeding a radio station?
This option sets the output device to "pause" to disable the "close"
method.  It falls back to "pause" then, which is specific to the
plugin.  Some plugins implement it by feeding silence.

If we're not doing this, and a new song is played after pause ends,
then you will hear the rest of the previous song.

Always use the same number of samples from each channel's ring
buffer.  This ensures that all channels are kept in sync.

Pass everything to the GLib logging library.  No direct stderr access.

The pointer is invalid if av_open_input_file() fails.

This is a very basic check, which only ensures that the path does not
begin with a slash, doesn't have double slashes and the special names
"." and ".." are forbidden.

Dots at the beginning of an URI segment are ok, as long as the special
names "." and ".." are not used.

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.