[FR] Support multiple languages for notifications

[T0mWz]

For the Dutch Sync-And-Share service, we requires a specific OpenID Connect claim on which basis we do auto provisioning of a user. When a new user try to login which does not have the required attribute, this user will now get an error message like; Required provisioning claim is not defined. (see: https://github.com/owncloud/openidconnect/blob/master/lib/Service/AutoProvisioningService.php#L97)

Would be nice when also the l10n language support is integrated.