Calling B2Body::SetLinearVelocity / SetAngularVelocity should awaken body

[kmgb]

Based on the current b2d source here: https://github.com/erincatto/box2d/blob/master/include/box2d/b2_body.h#L507

Currently, calling the SetLinearVelocity and SetAngularVelocity doesn't cause the body to move until it is awakened somehow. Bodies should wake up when either two functions are called.