Initial commit of Session/Authentication code

Plugin architecture with single Database-backed implementation.

source/lib/SihnonFramework/Auth/IUpdateable.class.php

@@ -0,0 +1,13 @@
+<?php
+
+interface SihnonFramework_Auth_IUpdateable {
+
+    public function addUser($username, $password);
+    
+    public function removeUser(Sihnon_Auth_IUser $user);
+    
+    public function changePassword(Sihnon_Auth_IUser $user, $new_password);
+    
+}
+
+?>