Jifty::Plugin::Authentication::PasswordAction::GeneratePasswordToken - generate password token
Looks up what Jifty::Plugin::Authentication::Password is configured to login via, username or email address, to know what form element to expect.
We need the email of the user we're fetching a token for, so we can return the salt.
Generate a token and throw it back to the browser. Also, return the user's password salt in $self->result->content.
Load up and return a YourApp::User object for the user trying to log in