-Rewritten KinematicBody2D::move to MUCH more efficient code.

-KinematicBody2D::move now properly recognizes collision exceptions and masks, fixes #1649
-Removed object type masking for KinematicBody2D
-Added a test_motion() function to RigidBody2D, allowing simlar behavior to KinematicBody2D::move there.

demos/2d/kinematic_char/colworld.gd

@@ -14,4 +14,5 @@ func _ready():
 
 func _on_princess_body_enter( body ):
 	#the name of this editor-generated callback is unfortunate
-	get_node("youwin").show()
+	if (body.get_name()=="player"):
+		get_node("youwin").show()