Unreachable state/point of graph warnings for group transitions

Group transitions cause "unreachable" warnings on the source transition point, e.g.:

StateMachine {
	State default_1
	State reachable_1
	TransitionPoint tp1_1
	Transition init: initial -> default_1
	Transition toReachable_1: my tp1_1 -> reachable_1 {
		triggers { <in1: p> }
	}
}