broker/Topic: class added

broker/Topic: String Topics replaced by Topic class
broker/Topic#parseTopic: access set to private
broker/SubscriptionsStoreTest: topic tests moved to own class
broker/TopicTest: containsExactly used
broker/TopicTest: TopicAssert class added
broker/TopicTest$TopicAssert#containsToken: method added
broker/TopicTest$TopicAssert#matches: method added

broker/src/main/java/io/moquette/server/ConnectionDescriptorStore.java

@@ -147,7 +147,7 @@ public class ConnectionDescriptorStore implements IConnectionsManager {
                     new MqttSubscription(
                             subscription.getRequestedQos().toString(),
                             subscription.getClientId(),
-                            subscription.getTopicFilter(),
+                            subscription.getTopicFilter().toString(),
                             subscription.isActive()));
         }
         result.setActiveSubscriptions(mqttSubscriptions);