% characters caused issues in backup/restore due to filenames being appended directly into a format string.
Reserved XML characters (<>&') caused issues in the S3 driver due to improper escaping.
Add a file with all common special characters to regression testing.
Any beginning literal portion of a filter expression is used to generate a search prefix which often helps keep the request small enough to avoid rate limiting.
Suggested by Mihail Shvein.
* Combine hardlink and non/compressed in synthetic tests to reduce test time and improve coverage.
* Change log level of hardlink logging to detail.
* Cast size in S3 manifest to integer.
