lib/sup: dont close log_io if nil/false
ncurses: move all references from Curses to Ncurses
ncursesw: COLOR_PAIR beats color_pair
textfield: dont try to set cursed value to nil
bounce: use first element of array for sensible bounce question
buffer: fix multi-key sequence handling
prepare 0.15.4
Merge branch 'develop' of github.com:sup-heliotrope/sup into develop