Add smaller test.png test-map

The current map is actually bigger than 16kb so we cannot transmit it. Add
a smaller test.png file that can be transmitted correctly.

Signed-off-by: David Herrmann <dh.herrmann@googlemail.com>
Fix QUIZ answers

Some answers didn't correctly include exactly 4 answers. Fix that.

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