Make sure that we refresh the screen atomically, since the emit()
function may be called by more that one threads at a time.
Also, modify the draw_bannerwin() method which used to fail in case the
window would become too small. Make sure that the provided offsets to
the window.addstr() method are properly bounded.
Closes#160: blinkenlights display is broken
Tested-by: Cyril Brulebois
Tested-by: Gaudenz Steinlin
Signed-off-by: Ilias Tsitsimpis <i.tsitsimpis@gmail.com>
Signed-off-by: Nicolas Sebrecht <nicolas.s-dev@laposte.net>