Merge pull request #4568 from deathbeam/proper-shutdown

Properly shutdown everything on window close

runescape-api/src/main/java/net/runelite/rs/api/RSGameEngine.java

@@ -32,4 +32,7 @@ public interface RSGameEngine extends GameEngine
 {
 	@Import("canvas")
 	Canvas getCanvas();
+
+	@Import("shutDown")
+	void shutDown();
 }