knotty2: Handle long lines of text and terminal window size changes

knotty2: Handle long lines of text and terminal window size changes

Long lines of text which wrapped on the terminal corrupted the output shown by
knotty2. This patch catches such errors by becomming aware of the terminal size.

It also catches terminal window size change events and adapting to those
changes using a signal handler.

Based on a patch from Jason Wessel with several tweaks and enhancements
such as use of chained signal handlers and covering all output messages.

Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>