Re-enable requirelogin() or similar function where necessary

In PR #250 the `requirelogin()` function was essentially disabled (it only attempts to load the token without doing any checks). It's purpose was to prompt for login if a token is unavailable and load the token. It has been disabled since login is no longer required for most of the functions it was used for. For example, adding a remote doesn't require login if it's not a GIN server.

We need to rethink the login requirements and enable it only when necessary.