Make the messagedb a bounded queue at 5000 msgs/device

// FREEBIE

src/main/resources/messagedb.xml

@@ -65,4 +65,8 @@
         <dropNotNullConstraint tableName="messages" columnName="message"/>
     </changeSet>
 
+    <changeSet id="3" author="moxie">
+        <sql>CREATE RULE bounded_message_queue AS ON INSERT TO messages DO ALSO DELETE FROM messages WHERE id IN (SELECT id FROM messages WHERE destination = NEW.destination AND destination_device = NEW.destination_device ORDER BY timestamp DESC OFFSET 5000);</sql>
+    </changeSet>
+
 </databaseChangeLog>