Simplify the definition of many build options.

Make sure glibc gives us all features.

Allows building without GLib.  This fails to compile currently,
because GLib is still used in the MPD core.

Avoid GLib.

No GLib memory allocation.

No GLib memory allocation.

All parameters seem mandatory, otherwise this call makes MPD crash.

Reduce GLib usage.

Don't use GTimer if the operating system is able to tell us the
uptime.

Fixes build tests on ia64 and mipsel by testing for endianness in a
more general / portable way.

Improve readability.

D'oh!

Fixes building with gcc-4.8
Signed-off-by: Natanael Copa <ncopa@alpinelinux.org>

getnameinfo() doesn't work well - it always returns "localhost".

Skip the global destructors.  We don't need them here - we bail out as
quickly as we can.

Replacing GLib macros.

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

Migrate the remaining callers to FatalError().

Reduces header dependencies.

Replaces GLib's GError.