[AC21.5] Implement FcConfig handling (95%)

[Stephen J. Turnbull]

APPROVE COMMIT 21.5

Thanks to Mike and Aidan for comments.  Doesn't seem any substantive
changes are needed, I'll try to work up some tests (but that's hard
with something that's as personal as font choice).

There is also a patch for gdbinit.in, but I don't trust it (as the
comment in the file says, "gdb sux ... gdb sux").  So I'll be doing a
separate patch for that.

Stephen J. Turnbull writes:

 > I'm going to run with this for a few days, and if I see no major
 > problems, I'll commit.
 > 
 > src/ChangeLog addition:
 > 
 > 2007-04-15  Stephen J. Turnbull  <stephen at xemacs.org>
 > 
 > 	* font-mgr.c (DestroyFontsetP): New enum.
 > 	* font-mgr.c (fontset_to_list): Add destroyp argument of that type.
 > 	* font-mgr.c (Ffc_font_list): Add argument.
 > 	* font-mgr.c (Ffc_font_sort): Add argument.
 > 
 > 	* font-mgr.h (fc_config): Declare new Lisp object type.
 > 	* font-mgr.c (print_fc_config):
 > 	* font-mgr.c (finalize_fc_config):
 > 	* font-mgr.c (fc_config_p):
 > 	* font-mgr.c (Qfc_configp):
 > 	 Implement it.
 > 	* font-mgr.c (syms_of_font_mgr):
 > 	* font-mgr.c (complex_vars_of_font_mgr):
 > 	* lrecord.h (lrecord_type_fc_config):
 > 	Initialize it.
 > 
 > 	* font-mgr.c (fc_config_create_using): New helper function.
 > 	* font-mgr.c (FCSTRLIST_TO_LISP_USING): New helper macro.
 > 	* font-mgr.c (Vfc_config_weak_list): Manage references to FcConfigs.
 > 
 > 	* font-mgr.c (Ffc_get_version):
 > 	* font-mgr.c (Ffc_config_create):
 > 	* font-mgr.c (Ffc_config_get_current):
 > 	* font-mgr.c (Ffc_config_set_current):
 > 	* font-mgr.c (Ffc_config_up_to_date):
 > 	* font-mgr.c (Ffc_config_build_fonts):
 > 	* font-mgr.c (Ffc_config_get_config_dirs):
 > 	* font-mgr.c (Ffc_config_get_font_dirs):
 > 	* font-mgr.c (Ffc_config_get_config_files):
 > 	* font-mgr.c (Ffc_config_get_cache):
 > 	* font-mgr.c (Ffc_config_get_rescan_interval):
 > 	* font-mgr.c (Ffc_config_set_rescan_interval):
 > 	* font-mgr.c (Ffc_config_app_font_add_file):
 > 	* font-mgr.c (Ffc_config_app_font_add_dir):
 > 	* font-mgr.c (Ffc_config_app_font_clear):
 > 	* font-mgr.c (Ffc_config_filename):
 > 	* font-mgr.c (Ffc_init_load_config):
 > 	* font-mgr.c (Ffc_init_load_config_and_fonts):
 > 	* font-mgr.c (Ffc_init):
 > 	* font-mgr.c (Ffc_init_reinitialize):
 > 	Implemented operations.
 > 	
 > 	* font-mgr.c (Ffc_config_destroy):
 > 	* font-mgr.c (Ffc_config_get_blanks):
 > 	Stub operations.