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.

Print the list of suffixes supported by each decoder, instead of
prining a list of all suffixes of all decoders with duplicates.

This plugin is based on "libmpcdec".

This plugin is based on "libmp4ff".

A decoder plugin should be named after the library which is used.

A decoder plugin should be named after the library which is used.

The "decoder" configuration block may contain the configuration of one
decoder plugin.

Preparing for per-plugin configuration sections in mpd.conf.

Increase code readability, always use the wrapper functions instead of
calling the plugin method pointers directly.

The decoder_plugin struct is used by both the MPD core and the decoder
plugin implementations.  Move it to a shared header file, to minimize
header dependencies.

There are a few problems left in this plugin:

- fluidsynth decodes in real time, while MPD prefers to buffer as
  quickly as possible; as a workaround, this plugin uses a timer
  object to synchronize with real-time playback

- I don't know yet how fluidsynth tells me when the song has ended

- the "soundfont" configuration setting is not yet documented, and it
  will likely change soon (in favor of a per-decoder configuration
  block)

We have two mod plugins now: modplug and mod.  Rename the latter to a
more useful name.

Renamed types, functions, variables.

Renamed functions and variables.

The "oggflac" plugin was enabled only if HAVE_FLAC_COMMON was
defined.  HAVE_FLAC_COMMON however is only an automake variable, and
is never available in decoder_list.c.  Make decoder_list.c depend on
HAVE_FLAC||HAVE_OGGFLAC instead.

Renamed functions and variables.

Renamed functions and variables.

Renamed variables.

MPD used to have a copy of the mp4ff library.  Since that has been
removed, AAC suport was disabled when there was no libmp4ff.  Separate
the libmp4ff test, and enable AAC support no matter if libmp4ff is
available.

Commit 1a4a3e1f moved decoders into a static array, but failed to
enable those plugins who did not have an init() method at all.
This patch corrects the "enabled" check.

All decoder_plugin structs are initialized at compile time, and must
never change.

Currently, there is no way to dynamically load decoder plugins, thus
we don't need a dynamic list to manage them.

The decoder_plugin structs must never change.  Don't work with
non-const pointers.

Don't return 0/-1 on success/error, but true/false.  Instead of int,
use bool for storing flags.

[mk: fixed indent, changed copyright statement, added autoconf test,
fixed includes paths, fixed 2 gcc warnings, don't close input stream
twice]

Don't compile the sources of disabled decoder plugins at all, and
don't attempt to register these.

Why have a "_func" prefix on all method names?  Also don't typedef the
methods, there is no advantage in that.

This is the last of the three variables.  Now we don't need
playerData.h anymore in most sources.