Changed to new line data structures (__LDATA and __LINE) and

Changed to new line data structures (__LDATA and __LINE) and
eliminated linked list representation of window (not useful).

SCCS-vsn: lib/libcurses/curses.h 5.17
SCCS-vsn: lib/libcurses/insch.c 5.8
SCCS-vsn: lib/libcurses/addbytes.c 5.12
SCCS-vsn: lib/libcurses/delch.c 5.9
SCCS-vsn: lib/libcurses/addch.c 5.9
SCCS-vsn: lib/libcurses/box.c 5.8
SCCS-vsn: lib/libcurses/erase.c 5.8
SCCS-vsn: lib/libcurses/delwin.c 5.8
SCCS-vsn: lib/libcurses/cr_put.c 5.12
SCCS-vsn: lib/libcurses/deleteln.c 5.12
SCCS-vsn: lib/libcurses/overlay.c 5.10
SCCS-vsn: lib/libcurses/overwrite.c 5.9
SCCS-vsn: lib/libcurses/insertln.c 5.11
SCCS-vsn: lib/libcurses/newwin.c 5.10
SCCS-vsn: lib/libcurses/scroll.c 5.8
SCCS-vsn: lib/libcurses/clrtobot.c 5.9
SCCS-vsn: lib/libcurses/clrtoeol.c 5.8