Replace Travis CI w/ Github Actions

[hybras]

Closes #77

I assume this pr blocks on #92

1. Please create github secrets for crates.io token, docker username, docker password. You likely want to create org secrets for reuse across repos. Rename the references to the secrets to use the correct name (search for ${{ }})
2. How is each workflow triggered? On push, commit, tag?
3. How exactly is docker being used in this project (dev, build, CI, test)? Its been a while since your latest travis run (and I assume docker image as well). If docker is completely extraneous, then both the workflows end up being the same, with different triggers.