Fixes Joram##314368.

Inserts messages in right order after a stamp reset.
Adds the missing interface.

joram/a3/rt/src/main/java/fr/dyade/aaa/agent/MessageComparator.java

+/*
+ * Copyright (C) 2022 ScalAgent Distributed Technologies
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or any later version.
+ * 
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ * 
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307
+ * USA.
+ *
+ * Initial developer(s): ScalAgent Distributed Technologies
+ * Contributor(s): 
+ */
+package fr.dyade.aaa.agent;
+
+public interface MessageComparator {
+  /**
+   * Compares the 2 messages for time ordering. 
+   * Returns true if the first message is earlier than the second, false otherwise.
+   * 
+   * @param m1  The first message.
+   * @param m2  The second message.
+   * @return  true if the first message is earlier than the second, false otherwise.
+   * @throws NullPointerException if an argument is null and this comparator does not permit null arguments
+   */
+  boolean isPrior(Message m1, Message m2);
+}