* autogen.sh: pass --enable-debug when autogen is used.
* configure.ac: added check for --enable-debug added sse and mmx
* gegl/gegl-debug.h: debug infrastructure like the one in clutter.
* gegl/gegl-init.h: added gegl_get_debug_enabled().
* gegl/gegl-init.c: (gegl_post_parse_hook), (gegl_arg_debug_cb),
(gegl_arg_no_debug_cb), (gegl_get_debug_enabled): added debug
infrastructure.
* gegl/gegl-utils.[ch]: removed old unused log infrastructure.

svn path=/trunk/; revision=2206