New: sync.blue® CardDAV server

The new sync.blue® CardDAV server supports receiving and providing company contacts. 1) Provide contacts via CardDAV: Contacts from different sources can now be merged on the sync.blue® CardDAV server and made available company-wide. In this way, company contacts can be made available to a wide variety of CardDAV-compatible users without having to operate a separate CardDAV server at great expense. 2) Receive contacts via CardDAV: Contacts can be synchronized between company software via CardDAV and then synchronized with other apps.