* Adding mail verification during account registration
* Added new dist file option for mail verification
* Added account confirmation page using tokens
* Added mail class into user class for password resets
* Moved password reset template
* Adjusted account registration page
* Adjusted user class for email confirmation
Also fixed a bug with smarty_cache_key not being used properly if smarty
is disabled. Key still needs to be available even if caching is disabled
Addresses #330 and prepare the ticket for invitation only system.
