-More strict argument type-checking, will make many bugs visible, fixes #1809

-added NOTIFICATION_INSTANCED

demos/2d/platformer/enemy.gd

@@ -56,7 +56,7 @@ func _integrate_forces(s):
 					state=STATE_DYING
 					#lv=s.get_contact_local_normal(i)*400
 					s.set_angular_velocity(sign(dp.x)*33.0)
-					set_friction(true)
+					set_friction(1)
 					cc.disable()
 					get_node("sound").play("hit")
 					

demos/3d/platformer/enemy.gd

@@ -45,7 +45,7 @@ func _integrate_forces(state):
 				state.set_angular_velocity( -dp.cross(up).normalized() *33.0)
 				get_node("AnimationPlayer").play("impact")
 				get_node("AnimationPlayer").queue("explode")
-				set_friction(true)
+				set_friction(1)
 				cc.disabled=true
 				get_node("sound").play("hit")
 				return