Bifrost#T36198: Create non-conflicting ServerId for objects with non-unique or long UID
Summary:
This fixes two cases:
- Activesync client creating an object with very long UID (more than 64 chars)
- Storage containing more than one copy of the same event.
Reviewers: #syncroton_developers, vanmeeuwen
Reviewed By: #syncroton_developers, vanmeeuwen
Subscribers: vanmeeuwen
Differential Revision: https://git.kolab.org/D473