Cleanup utilities. Introduce sxe-memory.h Move all the memory related utilities to sxe-memory.h so that sxe-utils.h can be included in contexts where the memory utils are not welcome. * src/sxemacs.h: Remove include for sxe-utils.h, lisp.h already does it. * src/lisp.h: Include new sxe-memory.h * src/sxe-utils.h: Remove xnew, xnew_atomic, xnew_array, xnew_atomic_array, xnew_and_zero, xzero, xnew_array_and_zero, xrealloc_array, alloca_array, xstrdup * src/sxe-memory.h: Add definitions removed from sxe-utils. Signed-off-by: Nelson Ferreira <nelson.ferreira@ieee.org>