Add restore procedure using Scylla Manager

[tnozicka]

The current restore procedure is fairly manual, slow and @zimnx mentioned that it has a size limit as well. We should migrate to using the Scylla Manager for the restore.

- [ ] Create design doc for restore using Scylla Manager
- [ ] Implement support for restore using Scylla Manager in the Operator
- [x] Replace sstable based restore procedure with manager