Migrate from 'Travis CI' to 'GitHub Actions'

[urda]

This PR migrates the project from Travis CI to GitHub Actions.

• It performs all the same steps as done on Travis CI
• It splits up the "work" as best as possible to reduce build times.
• It will run linting on all pushed commits and pull requests for master and develop.
• It will run testing on all push and pull requests for master and develop.
• It will run package-building only on a push to develop.
• It will run a single pass test designed for enforced pull requests.
• It uploads to codecov still.
• Instead of running all tests in a single "job", testing is broken up by database engine.
• References to travis removed.

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Overall, this seems a LOT nicer than Travis was. See links listed in #104 but, yeah it seems that GitHub actions will be the replacement here.

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This PR Closes #104

[codecov[bot]]

Codecov Report

Merging #105 (351df32) into develop (2fef3d6) will not change coverage. The diff coverage is n/a.

@@            Coverage Diff            @@
##           develop      #105   +/-   ##
=========================================
  Coverage   100.00%   100.00%           
=========================================
  Files            3         3           
  Lines           23        23           
=========================================
  Hits            23        23           

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Continue to review full report at Codecov.

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