Supply username and password in settings

[notnownikki]

We'd like to run django-swiftbrowser with a different authentication mechanism, so to avoid the user having to log in twice (once to our SSO, then to the user accessing swift), we'd like to store a username and password in the settings. If the login view finds these settings, it would log in automatically using them.

Is that a feature you'd accept? We're happy to do the work if so :)