Moved file validation to file.php

 - Now run on all files uploaded
 - Reinstated password if test for sha1 encryption
Many things today!

 - .htaccess
 - removed mail to vulnerability by removing element from view as it
was not being used
 - added whitelist and clean() function for XSS protection
(controller.php)
 - fixed parameter manipulation/XSS vulnerability on page.php to stop
users being able to create pages with code in them
 - fixed logic error in view.htm (comment[‘users’] does not work
(needed to be $u->avatar) otherwise could not view page with avatar on
it