From Travis to Github Actions

[skoudoro]

This PR should fix #338. The goal is to switch off Travis and start Github Actions.

[skoudoro]

• I need to squash a bit multiple commits.
• Xvfb works 🥳
• There is a strange version of FURY, as we can see here that's why CI's are failing. I do not understand where this strange version number of fury comes from.

[arokem]

Just a hunch: you might want to change your working directory after installing, and before running the tests, so that Python picks up the version from the installation and not from the source.

[skoudoro]

This PR is done, anyone wants to have a look?

@arokem, my version problem was due to this 2 lines. Only the commit was pulled, but with versionner you need the tag to have the right version. These 2 lines permit to fetch the whole repo

[Garyfallidis]

Done! Thx!