Prepare to migrate away from GLib.  Currently, we're still using GLib
as a backend.

The MPD core will add this as a prefeix.

Migrate the remaining callers to FatalError().

Replaces GLib's GError.

Don't use macro magic, don't dereference the block_param.

Eliminate the evil goto.

This is necessary for Ogg packets that span more than one page.

Move the raw buffer to struct shout_data.

Make it a local variable instead.

Pass audio_output objects around instead of void pointers.  This will
give some more control to the plugin, and prepares for non-blocking
audio outputs.

Consistent naming.

Move the "extern" declarations from output_list.c, for more type
safety.

No caller needs to write.

In the "vorbis" plugin, this is a copy of the old flush() method,
while flush() gets a lot of code remove, it just sets the "flush" flag
and nothing else.  It doesn't start a new stream now, which should fix
a few problems in some players.

Added a new optional parameter for the shout plugin called "url".

After popular demand, I've switched the order of "artist" and "title"
in the stream title.  There is no standard, and there is no reliable
way to parse those from the stream title.

This makes the plugin more responsive to control commands, because it
will listen to control events while waiting.

Replaced all occurrences of g_error() with MPD_ERROR() located in a new header
file 'mpd_error.h'. This macro uses g_critical() to print the error message
and then exits gracefully in contrast to g_error() which would internally call
abort() to produce a core dump.

The macro name is distinctive and allows to find all places with dubious error
handling. The long-term goal is to get rid of MPD_ERROR() altogether. To
facilitate the eventual removal of this macro it was added in a new header
file rather than to an existing header file.

This fixes #2995 and #3007.

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.

An asterisk means that this attribute should not be enforced, and
stays whatever it used to be.  This way, some configuration values
work like masks.

During the pause loop, manually sleep for 500ms if shout_delay()
returns a value greater than that.  Don't exhaust libshout's buffer.

Renamed all remaining CamelCase functions.

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.