Revert "remove v1". Add a possibility to login with a webview

[AlexViseven]

This commit reverts a removal of a webview on the auth screen

[tobiasKaminsky]

Will be done in a different way, aligned with Alex:
V2 will be used, but no external web browser, but internal web view.

[tobiasKaminsky]

@AlexViseven I think we can thus close this one?

[AlexViseven]

I need a part of the reverted code, so adding v2 changes to this pull request will probably be better. @tobiasKaminsky, what do you think?

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