Fixed closing homes to actually call the close on the homes. Updated the

lowest setting on the test dim function to b 1.

Fixes #438
Fixes #440

src/main/java/com/bwssystems/HABridge/plugins/mqtt/MQTTHome.java

@@ -42,6 +42,7 @@ public class MQTTHome implements Home {
 				handlers.get(key).shutdown();
 			}
 		}
+		handlers = null;
 	}
 
 	public MQTTHandler getMQTTHandler(String aName) {