[UPDATE] CSRF protection, more info in login notification

 * Adds CSRF protection for multiple pages, see bottom
 * Adds User/IP/Date & time to successful login notification
 * New config option for sitewide CSRF protection
 * Fixed a bug in the contact form
 * Lots of cleanup related to CSRF stuff
 * Increments config version
 * CSRF protection: register, contact, account edit, workers, notifications, and invites