`login_do` now uses a try/catch control structure instead of the
horrifying nested if/else control structure it used before. I'd think a
failed login attempt counts as an exception, so it should be fair to use
it here?
I have also removed the one session per user limit for now. I'm going to
replace it with a manual session manager in user settings later
hopefully, and some sort of periodically run script that deletes any
expired sessions from the DB, plus maybe other places where they get
deleted.
any `use experimental 'name'` instances have been removed too since
Mojolicious complains about your use of experimental features no matter
what anyways!
