* src/dlg/dlgwrap.c: Duplicate some feature test macros from
`dlg.c`, which must come first before loading standard headers. For
example, `freetype.h` loads `stdio.h` if compiled in debug mode.
* autogen.sh (copy_submodule_files): New script to copy all the
necessary source and include files from `submodules/dlg` to
`src/dlg`.
* src/dlg/dlgwrap.c: New wrapper file for `src/dlg.c`. It enables
the build of 'dlg' if the `FT_LOGGING` macro is defined.
* src/dlg/rules.mk: New sub-Makefile.
* builds/freetype.mk (DLG_DIR): New variable to include the
header files of the 'dlg' library.
(INCLUDES): Add `DLG_DIR`.
(FT_CFLAGS): Add `-std=c99' flag.
Include `src/dlg/rules.mk` file to build 'dlg' library.
(OBJ_S, OBJ_M): Add `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/ftoption.h, devel/ftoption.h (FT_LOGGING):
New macro to enable or disable the logging facility in FreeType.
Werner Lemberg
Alexei Podtelezhnikov
Priyesh Kumar