Configure when the debug CodeLens is displayed

[seanpoulter]

This PR adds a new setting to control when the debug CodeLens appears above a test. Set "jest.debugCodeLens.showWhenTestStateIn" to any of combination of "fail", "pass", "skip", "unknown" to your liking. It defaults to the current behaviour.

Can you think of a better name for the setting?

This will close #240.

[coveralls]

Pull Request Test Coverage Report for Build 371

• 19 of 19 (100.0%) changed or added relevant lines in 4 files are covered.
• 55 unchanged lines in 2 files lost coverage.
• Overall coverage increased (+0.2%) to 74.633%

---

Files with Coverage Reduction	New Missed Lines	%
src/extension.ts	4	68.57%
src/JestExt.ts	51	53.87%

Totals
Change from base Build 368:	0.2%
Covered Lines:	589
Relevant Lines:	753

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💛 - Coveralls

[seanpoulter]

Here's a screenshot of the auto-complete in .vscode/settings.json in action:

[orta]

I think the name makes sense

[orta]

I merged some PRs which caused a few conflicts

[seanpoulter]

Thanks for the follow-up on this one @orta. I've rebased and added one unrelated commit that modifies .gitignore. Hopefully we can sort out some of these regressions. 🥞🍴

[orta]

Cool yep, nice work 👍