Uncategorized tests should not default to expensive

[jsiirola]

Summary/Motivation:

Currently uncategorized pyutilib.th tests default to "smoke, nightly, expensive". This means that the "expensive" test jobs duplicate all of the tests that the smoke/nightly test jobs have already done, which seems redundant ('all' covers that use case). This PR changes the default so that uncategorized tests are marked as "smoke, nightly," but not expensive. This will reduce the amount of unnecessarily repeated tests in most testing setups.

Changes proposed in this PR:

• remove "expensive" as a default category

Legal Acknowledgement

By contributing to this software project, I agree to the following terms and conditions for my contribution:

1. I agree my contributions are submitted under the BSD license.
2. I represent I am authorized to make the contributions and grant the license. If my employer has rights to intellectual property that includes these contributions, I represent that I have received permission to make contributions and grant the required license on behalf of that employer.

[jsiirola]

This PR is meant to seed a discussion around managing test suites. This is a 1-line PR with a fairly significant impact. As such, I am hoping to hear from all the reviewers before we entertain merging it.

[coveralls]

Coverage remained the same at 64.004% when pulling 72ff932 on nightly_not_expensive into 2e25e1d on master.

[coveralls]

Coverage remained the same at 64.004% when pulling 72ff932 on nightly_not_expensive into 2e25e1d on master.

[coveralls]

Coverage remained the same at 64.004% when pulling 72ff932 on nightly_not_expensive into 2e25e1d on master.

[coveralls]

Coverage remained the same at 64.004% when pulling 72ff932 on nightly_not_expensive into 2e25e1d on master.

[codecov-io]

Codecov Report

Merging #46 into master will not change coverage.
The diff coverage is 0%.

@@           Coverage Diff           @@
##           master      #46   +/-   ##
=======================================
  Coverage   64.94%   64.94%           
=======================================
  Files          87       87           
  Lines        8726     8726           
=======================================
  Hits         5667     5667           
  Misses       3059     3059

Impacted Files	Coverage Δ
pyutilib/th/pyunit.py	47.93% <0%> (ø)	⬆️

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[blnicho]

I am in favor of this change in default behavior. Reducing some redundancy in our testing infrastructure seems like a win.