Get tests working on github

[rbooth200]

This pull request fixes the automatic tests and sets up Github to run them automatically on pushes

[Schulik]

I haven't reviewed everything, as in this merge request github seems to double-count a ton of code, but probably as the code is working mostly fine. I'd just request to roll back some of the loop maximum changes from num_cells+2 to num_cells+1, as the last ghost cell often creates problems, and doesn't need to be updated in some cases anyway (like the rad transport)

[rbooth200]

I can't because the collisional heating test with radiative transfer fails if I do. The problem is that with a limit of ncells+1 the temperature of the last ghost cell is not constrained, resulting in a singular matrix.

With the current implementation the hydro works properly, as demonstrated by the shock-tube tests, and the radiation works properly as demonstrated by the irradiation tests, so I don't think there is really a problem with the current implementation.