menumanager: fix right click/swap issues (#866)

* menumanager: fix possible concurrent modification exception, add small
optimization for left click entries, and cleanup

* menumanager: stop entries from swapping in the right click menu if the
swapFrom is already the first option

* Revert "rsclientmixin: make use of edited menuopened event variables"

This reverts commit d2cd11a7

* menumanager: set event entries in menuopened event to prevent conflicts

* menumanager: remove type change, and improve performance

* menumanager: add field to set priority level to prevent conflicts

runelite-mixins/src/main/java/net/runelite/mixins/RSClientMixin.java

@@ -1304,7 +1304,6 @@ public abstract class RSClientMixin implements RSClient
 		final MenuOpened event = new MenuOpened();
 		event.setMenuEntries(getMenuEntries());
 		callbacks.post(event);
-		client.setMenuEntries(event.getMenuEntries());
 	}
 
 	@Inject