* autogen.sh (copy_submodule_files): New script to copy all the
necessary dlg's source and include files from `submodules/dlg' to
`src/dlg'
* src/dlg/dlgwrap.c: A wrapper along `src/dlg.c', it enables the
dlg's build only when `FT_LOGGING' maro is defined.
* src/dlg/rules.mk: Makefile to compile dlg library along with
rest of FreeType's modules.
* builds/freetype.mk (DLG_DIR): New variable to include dlg's
header files.
(INCLUDES): Added `DLG_DIR'.
(FT_CFLAGS): Added `-std=c99' flag.
Include `src/dlg/rules.mk' file to build dlg.
(OBJ_S, OBJ_M): Added `DLG_OBJS_M' and `DLG_OBJS_S'.
* builds/toplevel.mk: For builds directly from the git repository
we need to copy files from `submodule/dlg' to `src/dlg
* {include/freetype/config, devel}/ftoption.h (FT_LOGGING): A new
macro to enable or disable the logging facility in FreeType.