lib: add classic-controller reports

The classic controllers are already supported by linux-3.11 kernels so add
parser support. They're very similar to pro controllers but additionally
support analog TR/TL triggers. The thumb buttons are not available,
though.

Signed-off-by: David Herrmann <dh.herrmann@gmail.com>
xwiishow: refresh screen on error/init prints

We need to call refresh() after any info/error prints. Furthermore, the
screen-clear should be done _before_ opening the first input events.

This fixes bugs were errors during startup were not printed correctly
because they either ended up in the internal cache or were cleared during
startup.

Signed-off-by: David Herrmann <dh.herrmann@gmail.com>
xwiishow: add classic-controller support

Reuse the pro-controller area and parsers to also show classic controller
and classic controller pro information.

Signed-off-by: David Herrmann <dh.herrmann@gmail.com>
lib: add nunchuk parsers

Nunchuk data is supported since linux-3.11 by the kernel so parse it and
forward it to users.

Nunchuk data includes two buttons (C+Z), an analog stick and a separate
3-dimensional accelerometer.

Signed-off-by: David Herrmann <dh.herrmann@gmail.com>
xwiishow: visualize nunchuk data

Nunchuk data is supported by libxwiimote so display it similar to existing
analog sticks and accelerometers.

Signed-off-by: David Herrmann <dh.herrmann@gmail.com>