+ 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).
+ improve fix for FreeBSD gnu/98975, to allow for null pointer passed
to tgetent() (report by Rong-en Fan).
+ update tack/HISTORY and tack/README to tell how to build it after
it is removed from the ncurses tree.
+ fix configure check for libtool's version to trim blank lines
(report by sci-fi@hush.ai).
+ review/eliminate other original-file artifacts in cursesw.cc, making
its license consistent with ncurses.
+ use ncurses vw_scanw() rather than reading into a fixed buffer in
the c++ binding for scanw() methods.
+ eliminate fixed-buffer vsprintf() calls in c++ binding.
