Includes general improvements, bug fixes:
- Retry with the admin ssh port on network unreachable too. #377
- Output backup utils version on backup and restore #384
- Check filesystem supports hardlinks #388
- Switch back to optimised restore route calculation #389
- Optionally log verbose output to a file instead of stdout #391
- Switch back to optimised backup route calculation #392
- Remove check for git from ghe-ssh #393
- Use remote's mktemp to create temp dir on remote host #395