Fixing how the backend uses data types

Highlights

• The new ServiceX background is better about paying attention to the results-format tag - which was not being properly handled by the front-end stack. This fixes that up.
• Small fixes to metadata, package version limits, etc.

What's Changed

• Be consistent about root file type by @gordonwatts in #57
• New Release Prep by @gordonwatts in #58

Full Changelog: 2.1...2.2