+ modify _nc_panelhook() data to account for a permanent memory leak.
+ fix memory leaks in test/demo_menus
+ fix most warnings from Klocwork tool (report by Larry Zhou).
+ modify configure script CF_XOPEN_SOURCE macro to add case for
"dragonfly" from xterm #236 changes.
+ modify configure script --with-hashed-db to let $LIBS override the
search for the db library (prompted by report by Samson Pierre).
+ change test/ditto.c to use openpty() and xterm.
+ add locks for copywin(), dupwin(), overlap(), overlay() on their
window parameters.
+ add locks for initscr() and newterm() on updates to the SCREEN
pointer.
+ finish table in curs_thread.3x manpage.