avltree-omap: New module. * lib/gl_avltree_omap.h: New file. * lib/gl_avltree_omap.c: New file. * lib/gl_avltree_ordered.h: Code moved to here from lib/gl_avltree_oset.c. Parameterize. * lib/gl_avltree_oset.c: Include gl_avltree_ordered.h. * lib/gl_anytree_omap.h: New file. * modules/avltree-omap: New file. * modules/avltree-oset (Files): Add lib/gl_avltree_ordered.h. (Makefile.am): Add gl_avltree_ordered.h to lib_SOURCES.