Detangling creation

There have been too many dependencies between race, class, and creature
when it comes to skills, attributes, health, etc.  This cleans up those
dependencies by making the client make decisions before they can
instantiate a race, clazz, or creature object.

Further work needed
- Separating Creature creation from Gameplay
- Fleshing out feats, powers, racial and clazz bonuses
- Implementing above into the simple GUI