Switch to GitHub Actions

[robbievanleeuwen]

Discussed in #60

^{Originally posted by Spectre5 February 12, 2021}
@robbievanleeuwen what are you thoughts on switching from travis CI to the native github actions? After we add some lint/code quality checks to the repository, I'll follow up with another PR to add those checks to the CI pipeline. Travis is fine, I'm just more familiar with github actions. I'm mostly curious if there is a specific reason you're using travis instead?

[ccaprani]

After a steep learning curve, I've implemented a full CI/CD workflow in GHA here: https://github.com/MonashSmartStructures/ospgrillage Some/most/all could be adopted here to get up and running quickly.

[robbievanleeuwen]

Implemented with #148