the xx layer added, handle "ic" differently, compression added to zapple

SCCS-vsn: usr.bin/window/wwinschar.c 3.17
SCCS-vsn: usr.bin/window/wwscroll.c 3.22
SCCS-vsn: usr.bin/window/lcmd2.c 3.17
SCCS-vsn: usr.bin/window/wwdelchar.c 3.14
SCCS-vsn: usr.bin/window/tth29.c 3.7
SCCS-vsn: usr.bin/window/ttgeneric.c 3.38
SCCS-vsn: usr.bin/window/tth19.c 3.20
SCCS-vsn: usr.bin/window/tttermcap.c 3.10
SCCS-vsn: usr.bin/window/wwtty.c 3.13
SCCS-vsn: usr.bin/window/wwredraw.c 3.10
SCCS-vsn: usr.bin/window/tt.h 3.21
SCCS-vsn: usr.bin/window/wwend.c 3.12
SCCS-vsn: usr.bin/window/ww.h 3.53
SCCS-vsn: usr.bin/window/wwupdate.c 3.24
SCCS-vsn: usr.bin/window/wwinit.c 3.33
SCCS-vsn: usr.bin/window/Makefile 5.4
SCCS-vsn: usr.bin/window/ttzapple.c 3.2