Add Fire, Rotation. Document Health, Hunger, Position, Velocity

components-system branch: Big thanks to @Zidane for starting components up
Documented some values with "value in {link org.spongepowered.api.math.Vector3i Vector3i}" due to the fact that new people may not be used to using Vector3i
Rotation could be part of Position as a `Vector2f` with components `(yaw, pitch)`