add GitHub action

[twpayne]

Eventually, this could replace Travis. It includes a build and test check, and invokes golangci-lint with its default configuration.

[codecov]

Codecov Report

Merging #45 into master will not change coverage.
The diff coverage is n/a.

@@           Coverage Diff           @@
##           master      #45   +/-   ##
=======================================
  Coverage   80.55%   80.55%           
=======================================
  Files           1        1           
  Lines         432      432           
=======================================
  Hits          348      348           
  Misses         60       60           
  Partials       24       24           

---

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[bmatcuk]

Thanks for the PR, @twpayne... I haven't used github actions before - does it offer any benefits over travis?

[twpayne]

The main advantages over Travis is that GitHub Actions are a lot faster, support Windows, and are under active development.

[bmatcuk]

FWIW, travis also supports Windows and is actively developed... but I'll concede that it's slow =) I'll take a look into github actions.

[twpayne]

Closing this with ETIMEDOUT, please re-open if needed.