When there are standardized headers, use these instead of the bloated
os_compat.h.

git-svn-id: https://svn.musicpd.org/mpd/trunk@7356 09075e82-0dd4-0310-85a5-a0d7c8717e4f

This reduces the text size of the binary slightly when zeroconf
support is not built, and keeps the interface code cleaner as
well.

git-svn-id: https://svn.musicpd.org/mpd/trunk@7133 09075e82-0dd4-0310-85a5-a0d7c8717e4f

Also, lower the impact of compiling this w/o zeroconf by
making the init/teardown functions static no-ops.

Eventually, we should separate the Bonjour and Avahi
code into separate files and have callbacks registered
for each one, avoiding the #ifdef mess we have now...

git-svn-id: https://svn.musicpd.org/mpd/trunk@7132 09075e82-0dd4-0310-85a5-a0d7c8717e4f

This will make refactoring features easier, especially now that
pthreads support and larger refactorings are on the horizon.

Hopefully, this will make porting to other platforms (even
non-UNIX-like ones for masochists) easier, too.

os_compat.h will house all the #includes for system headers
considered to be the "core" of MPD.  Headers for optional
features will be left to individual source files.

git-svn-id: https://svn.musicpd.org/mpd/trunk@7130 09075e82-0dd4-0310-85a5-a0d7c8717e4f

git-svn-id: https://svn.musicpd.org/mpd/trunk@6112 09075e82-0dd4-0310-85a5-a0d7c8717e4f

git-svn-id: https://svn.musicpd.org/mpd/trunk@5834 09075e82-0dd4-0310-85a5-a0d7c8717e4f

git-svn-id: https://svn.musicpd.org/mpd/trunk@5238 09075e82-0dd4-0310-85a5-a0d7c8717e4f