#765994 by hunmonk: Non-authenticated role is hidden in user profile form even when 'Set password' is unchecked. also backported the missing logic for the user admin form from 6.x

remove unnecessary db_query -- admins validating a user account shouldn't trigger an account login, either.

#564062 by Matthew Davidson, hunmonk: Admin created accounts should have password length validation.

#368699 by hunmonk: re-send validation link always appears if non-authenticated role is set to auth user.

#320162 by xurizaemon: LoginToboggan prevents use of spaces in passwords, breaking passphrase functionality.

#291001 by hunmonk: Allow One Time Login To Be Used Only Once. the previous solution was very broken --this one has been more well tested.

#238660 by hunmonk: Allow user admins to re-send validation e-mail. thanks to manoloka for sponsoring the work on this patch.

#204383 by hunmonk: User can register with email address. cleaned up validation code of duplicate username/email for the case where login with email is enabled. ripped out some duplicate code.

#215999 by hunmonk: Login on Access Denied resets itself when module listing page is submitted and there is a module dependency for logintoboggan. broke this check out into a FAPI validation function, and added a check to see if the module checkbox is disabled.

clean up validation problems with users changing their username/email to another user's username/email when login w/ email is enabled.

#204600 by hunmonk: theme_lt_username_title can not be overwritten in template.php. replace all hardcoded theme calls with proper calls to theme().

#204383 by hunmonk: User can register with email address -- doc error. removed faulty doc -- users have always been able to register w/ an email address for a username. tightened check for usernames that are already taken as email addresses by another user.

#198551 by hunmonk: User registration guidelines not on top of registration form. properly re-weight the help text.

make username/password title/description themable, and don't clobber exiting attributes. some comment cleanup.