Add support for large files, plus some locale improvements.

Add support for large files, plus some locale improvements.

* dispatch.c, lwlib-Xaw.c, lwlib-Xlw.c, lwlib-Xm.c, lwlib.c, xlwmenu.c,
xrdb-cpp.c, xrdb.c:
Include <config.h> before any system include files.

* lwlib-Xm.c, lwlib.c:
Do not include <stdlib.h> or <string.h>, as <config.h> does this.