Fixed merge conflict.

Fixed mistake in log out example image. Oops.

Added most of the screenshots for Chapter 6. Sorry the usernames don't match - does it matter for a community-written book? :)

Merge pull request #5 from rolandixor/24ddade124a3d26a135e3e005719a3e3be2c0645 Nothing major

Added CREDITS file and added some stuff to Book.txt

Merge pull request #4 from minitech/master Cover page!