Moving stuff over to new entity system

Yesterday I got the monster/projectile collision stuff moved over to the new entity system. I took the existing tests that me and Sam did and rejigged them. Pathfinding has also been taken over.

Unit testing each action was fairly easy, but doesn't give you much confidence that the entire interaction will work - pathfinding and shooting both involve a few different components talking to each other. To fully test this I've added some integration tests. They still run as fast as the unit tests, but they involve interactions between several classes (which should be a no-no in a unit test).

There are still a few tests that need to be added, or rather there are still things we need to work out. At the moment each action checks its user and target entities for certain components. If they exist it proceeds as normal. If it can't find them however, it just returns from its DoAction method. We'll need to think about cases where actions can act on entities that have a subset of the components they require to work fully, and what should happen when one or several can't be found.

Are both of you up for a chat later on this afternoon? Thinking about 1700 onwards...?