Update to ncurses-5.0-20000401:

Update to ncurses-5.0-20000401:
 o change unctrl() to render C1 characters (128-159) as ~@, ~A, etc.
 o trace() function is provided only if TRACE is defined, e.g., in the debug
   library.  Modify related calls to _tracechar() to use unctrl() instead.