fix package, add hut4 rules file

[codegoblin]

this silos the hut4 rules into a single file

[cdidyk]

I'm not sure what came of the discussion on slack, but it sounds like it makes more sense to leave the bletchley-level linter/styles "pristine" (instead of forcing hut4's modifications on it) and keeping hut-specific modifications separate. I'm guessing that would happen through hut-specific packages?

Also, what do you think about describing the process for modifying hut-specific (and bletchley-wide) style guides in the wiki?

[cdidyk]

Oh, I forgot to say that I +1 this PR. Even if the answers to my questions above change some things, I don't think those changes would be a big deal nor should they stand in the way of us getting going customizing this guide.

[codegoblin]

You don't have to build a new package, you just need to stipulate extend: bletchley/hut4 ... if you just want all the top-level, non-hut rules you would stipulate extend: bletchley in the .eslintrc

I totally agree with the readme expansion. Maybe I'll get some time to do that today.

[cdidyk]

Groovy