WavPack tags are always APEv2, by definition.  Reuse the tag_table
from tag_ape.c, instead of rolling our own.

Prepare for big CUESHEET tags.

The new method pair() receives an arbitrary name/value pair.  Support
for this is being added to a few decoder plugins.

Remove clutter from wavpack_scan_file(), and use a (large) fixed
buffer for the tag item.

Pass a callback table to scan_file() and scan_stream(), instead of
returning a tag object.

For MPD's new floating point support: when a decoded wavpack file
needs to be resampled, don't convert float to int and back to float.

Use local variable "is_float".

Add GMutex, GCond attributes which will be used by callers to
conditionally wait on the stream.

Remove the (now-useless) plugin method buffer(), wait on GCond
instead.  Lock the input_stream before each method call.  Do the same
with the playlist plugins.

It used to ignore the decoder_data() return value.

libwavpack provides int32_t samples, and wants uin32_t for sample
counts.

.. and remove one indent level.

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.

Pass the current URI to wavpack_open_wvc().

Use input_stream.uri.

Make it X_decoder_plugin.c.

This function replaces the replay_gain_info parameter for
decoder_data().  This allows the decoder to announce replay gain
changes, instead of having to pass the same object over and over.

Major API redesign: don't let the caller allocate the input_stream
object.  Let each input plugin allocate its own (derived/extended)
input_stream pointer.  The "data" attribute can now be removed, and
all input plugins simply cast the input_stream pointer to their own
structure (with an "struct input_stream base" as the first attribute).

Remove the data_time parameter from decoder_data().  This patch
eliminates the timestamp counting in most decoder plugins, because the
MPD core will do it automatically by default.

First multiply the floating point return value of
decoder_seek_where(), then cast to integer.

Use the signed C99 type int8_t instead.

This patch prepares support for floating point samples (and probably
other formats).  It changes the meaning of the "bits" attribute from a
bit count to a symbolic value.

Let the audio_check library verify the audio format in all (relevant,
i.e. non-hardcoded) plugins.

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.

Remove the OPEN_2CH_MAX option.  MPD's support for surround sound is
still clunky, but we're working on it.

MPD has been supporting 32 bit samples since version 0.15.  This patch
changes one check, and removes the 32->24 conversion code.

Note that WavPack floating point samples have 32 bits, and MPD doesn't
have a special check for floating point - therefore, this WavPack
plugin still returns 24 bit integer samples as before (until we have
float support in the MPD core).

It makes no difference right now, but we're about to add an endianness
flag and will want to make sure it's correctly initialised every time.

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.

The wavpack library seems to use the .wvc stream even if the OPEN_WVC
flag is not set.  In this case, pass NULL to be sure libwavpack won't
use it.

Removed all allocation functions, xwrite(), xread(), ARRAY_SIZE().
Those have been superseded by GLib.

Use GLib's G_GNUC_UNUSED instead of gcc.h's mpd_unused.