Rename HAVE_WINDOWS to host_is_windows for consistency.
Use 'yes' as true value instead of '1' for this variable.
Use test on this variable instead of case where applicable.

Remove compatibility code.

This change adds two configuration options:

  --with-eventloop=[glib|internal|auto]
  --with-pollmethod=[epoll|auto]

First allows switching between GLib event loop and internal one.
Second chooses backend to use for internal event loop.
Conditional compilation symbols are changed accordingly.
Additional helper macro MPD_OPTIONAL_FUNC_NODEF is added as well.

The option "--enable-fluidsynth" was documented to be "auto" by
default, when it was really "no".

bzip2-compressed tarballs are obsolete, xz is better and widely
understood.

Prior to version 0.3, the "length" callback returned a "long" instead
of AFfileoffset.  Now that this API bug fix is a few years old, let's
drop 0.2 support for good.

Without -Werror, clang will not fail on -ftree-vectorize.

Allows advanced compiler optimization.

Most importantly: always disable C++ exceptions.  It was surprising to
see MPD terminate due to an unexpected exception.

There hasn't been a maintainer for this plugin for years.  It may even
fail to build.

Fixes the OpenAL detection which was broken because enable_osx was
uesd which was set later.

Finally fixes the regression by commit c1f4f1fd.

Restore the "mpcdec" decoder plugin that was accidently broken since
commit 8ead8f7e.

Make the third argument to AC_CHECK_LIB() non-empty to disable its
default handler.

The header glib_compat.h is now obsolete and can be removed.

This plugin has been defunct ever since Last.fm changed their
protocol.  Since there is no volunteer willing to fix the plugin, I'm
removing it now.

Remove all #ifdefs.  Old versions of libpulse are not being tested,
and thus I'm removing support.