small changes to factory and implemented rmi awareness with a simple register/deregister program

rmi_Awareness/register_to_server.java

@@ -0,0 +1,13 @@
+package rmi_Awareness;
+
+import java.rmi.Remote;
+import java.rmi.RemoteException;
+
+/**
+ * Created by Giovanni on 01/12/2014.
+ */
+public interface register_to_server extends Remote {
+
+        void register (call_me_back obj) throws RemoteException;
+        void deregister (call_me_back obj) throws RemoteException;
+}