broker/MapDBPersistentStore: Interfaces used for the Constructors

broker/IStore: Interface added for MapDBPersistentStore
broker/ProtocolProcessorBootstrapper: class loader for store added
broker/ISessionsStore#mapToGuid: moved to IMessagesStore
broker/ProtocolProcessorBootstrapper: getter used for SessionStore
broker/Server: getter for processor added
broker/ProtocolProcessor: getter added for Stores

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

@@ -329,4 +329,7 @@ public class Server {
         return m_processorBootstrapper.getConnectionDescriptors();
     }
 
+    public ProtocolProcessor getProcessor() {
+        return m_processor;
+    }
 }