Re-style codebase: validphys

Created by: scarlehoff

In this PR I've run black and isort against most of validphys.

I've gone through all changes. I've added fmt: off in a couple of places where I didn't like the changes that black did and fixed several strings (mostly those that ended up looking "like" "this").

I've skipped the tests and the scripts since they are in a category of their own and I prefer to hace some pre-approval of the people involved before spending more time looking at infinite diffs.

I've done validphys first because as far as I can see there are no big PRs left touching vp (other than the commondata parser, but that's on me). We could leave out specific files (by putting fmt: off in) that people might want to keep unchanged because they are working on them.