(#17824) PMT should not prefer pre-release versions to existing stable versions.
Adding a couple additional tests for supplied version constraints.
Certain server configurations are less diligent about whitespace.

This is primarily a fix for our acceptance testing environment.
Merge pull request #1654 from pvande/tickets/master/17824-pmt-should-not-prefer-prereleases

(#17824) PMT should not prefer pre-release versions over existing stable versions