Östgötatrafiken: Adapt to new login page

[robho]

Östgötatrafiken now supports three ways to log in/authenticate:

• An e-mail address
• A username (for legacy users (such as me))
• Facebook login

Bankdroid only supports e-mail/username login.

(I haven't tested e-mail login, but I expect it to work the same way as for username logins)

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You may want to add Östgötatrafiken to the list of supported "banks" on the play store.

[robho]

New version better?

Or, were you thinking of one giant String.format()? (I didn't find that to improve readability)

[goober]

Sorry, I was too tired yesterday when I reviewed you PR. I agree with you that your initial version was better.

[goober]

Thank you!