Rework config file parsing and test running a bit.
Change error reporting logic a bit.

Only print a FAILED message if a test unexpectedly fails.
Move test running into classes.

Not convinced this is the best way, but I think its a bit neater than it
was before.
Validate config items.
Merge pull request #3 from tom5760/tests-rework

Tests rework
Copyright updates.
Update README.md
Updated test.xml to use pass rather than accept.