Delete pic utils in register.php, use utils-pic.php instead
Fix JavaScript reference to TRUST_REMOTE_USER constant from PHP
Rewrite register.php to skip email checking stage (#9), report errors

* Registration is now a one-step process; there won't be any phantom
  rows in user_info with it
* The page will check for errors such as whether the email or username
  has been taken, and report a specific error message if so
* Various checks for equality have been tightened out of paranoia about
  PHP type juggling
Merge remote-tracking branch 'origin/master'