Added Google Authenticator

Google Authenticator has been added to the login.
New Files
Class:  files/class.gauth.php
Widget: files/elements/widgets/ googleAuth.php
Settings: html/settings/2-step.php
Modified Files
Class:  files/class.user.php
Tabs: files/elements/tab_settings.php
Index: html/index.php

Added two columns to table users
g_auth int(1)
g_secret varchar(255)