Fix build issues with GCC 4.8 and dbtool.

	* doc/Makefile.in: Regenerated
	* gcc_plugin/feature-extract.cpp: Replace uses of GCC_MINOR with
	GCC_VERSION.
	Fix GCC 4.8 headers.
	* mageec/Makefile.am: Link with libmageec_learner before libmageec.
	* mageec/Makefile.in: Regenerated.