+ fix compiler warning for clang 2.9
+ improve merging of mouse events (integrated patch by Damien
Guibouret).
+ correct mask-check used in lib_mouse for wheel mouse buttons 4/5
(patch by Damien Guibouret).
+ 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).
