Fix transitions not happening if the ESCRoom has no ESC script (#485)

Fixes godot-escoria/escoria-issues#95

game/rooms/room16/esc/right_exit.esc

@@ -0,0 +1,3 @@
+:exit_scene
+play_snd res://game/sfx/sounds/doorOpen_2.ogg
+change_scene "res://game/rooms/room17/room17.tscn"

game/rooms/room16/esc/room16.esc

@@ -6,3 +6,11 @@
 	set_angle player 90
 	stop
 
+
+
+> [eq ESC_LAST_SCENE room17]
+	teleport player r16_r_exit
+	# Set player look down
+	set_angle player 180
+	stop
+

game/rooms/room16/room16.tscn

@@ -68,8 +68,8 @@ script = ExtResource( 5 )
 global_id = "r12_l_exit"
 
 [node name="r_door" parent="Hotspots" instance=ExtResource( 8 )]
-global_id = ""
-esc_script = ""
+global_id = "r16_r_exit"
+esc_script = "res://game/rooms/room16/esc/right_exit.esc"
 
 [node name="ESCLocation" type="Position2D" parent="Hotspots/r_door"]
 position = Vector2( 1231.78, 360.624 )