Added source code for classes that were previously not included.

The code for the missing classes is included to make exploration of the code easier.

Don't scroll down too far in Scenario.java or you'll see who the villains are.  (There is a large patch of whitespace and a spoiler warning to avoid accidental discovery of whodunnit.)
Merge branch 'master' of github.com:UQdeco2800/tutorial-thekey-mock-public