src/xxd: remove unused *.mak files for
src/xpm: remove XPM library for Windows
arabic.c/h: clean up pre-C99 syntax.
src/bigvim[64].bat: remove Windows batch scripts
src/Make_sas.mak: remove Amigo make file
src/Make_manx.mak: remove Amigo make file
src/Make_mvc.mak: remove Windows make file
src/blowfish.c: cleanup blowfish.c
src/os_mac_rsrc: remove Mac icons