Add Auto-Provisioning

[AutoImport-wonko21]

Either via URL (see http://dmfs.org/wiki/index.php?title=Auto-provisioning )
or via a prepared config file

Options
The dav url (seperate vor card/cal/task)
The user
The Password (hashed?)
The Server Cert (For self signed)

Of course the Privisioning shall allow combinations of above where the rest ist completed with the ui

[devvv4ever]

Something like that is already in development for DAVdroid! This will greatly simplify the setup process. See #148 for more details.

[rfc2822]

Indeed, support for well-known URIs is coming, and support for current-user-principal is already available.