CI is totally buggered

[tebello-thejane]

We have basically given up on Travis-CI as it has a lot of noisy failures.

• Are we trying to support too many GHC versions?
• And what about the jobs which just decide to fail on whim?

Get this shit stable and fixed, so that we don't ignore valid failures due to all this noise.

[mithrandi]

I put together an initial stab at this with Github Actions; next up is widening the matrix.

[tebello-thejane]

You left out stack?

[tebello-thejane]

I ain't never heard of GA before. Perhaps I'll give stack a stack.

[mithrandi]

Something like this will probably do the trick: https://kodimensional.dev/github-actions