Jigsaw Enhancements

- Added keepEntity property for jigsaw connectors. When set to true, mobs spawned will not despawn
- Fixed jigsaw entities being spawned off-center

src/main/java/com/volmit/iris/object/IrisJigsawPieceConnector.java

@@ -45,6 +45,10 @@ public class IrisJigsawPieceConnector
 	@Desc("Pick an entity to spawn on this connector")
 	private String spawnEntity;
 
+	@DontObfuscate
+	@Desc("Stop the entity from despawning")
+	private boolean keepEntity;
+
 	@DontObfuscate
 	@MaxNumber(50)
 	@MinNumber(1)