INCLUDES is the right way to add to CFLAGS, not DEFS.
	Also there are bugs with '+=' in makefiles.

	Got rid of DEFS line by moving G_LOG_DOMAIN setting into INCLUDES.
	Removed redundant -I from INCLUDES.

	This fixes an annoying bug where autoconf's DEFS, which includes
	the important -DHAVE_CONFIG_H, was lost.  (due to += weirdness)