Workaround: mcMMO bleed effect.

When GP cancels the damage event, mcMMO still applies "bleed" effect to
entities.  Trying to work around this by reducing priority so that
hopefully GP code will run before mcMMO code.

src/me/ryanhamshire/GriefPrevention/EntityEventHandler.java

@@ -502,7 +502,7 @@ class EntityEventHandler implements Listener
 	}
 	
 	//when an entity is damaged
-	@EventHandler(ignoreCancelled = true, priority = EventPriority.HIGHEST)
+	@EventHandler(ignoreCancelled = true, priority = EventPriority.LOWEST)
 	public void onEntityDamage (EntityDamageEvent event)
 	{
 		//monsters are never protected