Remote tool testing enhancements

[mvdbeek]

I'll collect some things as I encounter them.

• Allow passing in a test history. Otherwise you'll end up with one history per test, meaning > 1000 for a decent sized server if you're testing all tools
• Fall back to local test data if Galaxy version isn't compatible with remote test data fetching/uploading
  - [ ] Hash and check if we already used the test data, avoids re-uploading same file over and over (not sure if in interactor or in ephemeris ...)

[mvdbeek]

This is ready for review, and should be backported to 19.01, otherwise targeting external Galaxy < 19.01 with the galaxy interactor will fail.

[jmchilton]

Switched tag to 19.01 since it was backported.