Add lint groups to Q#

[orpuente-MS]

This PR adds the necessary infrastructure to define lint groups. It also adds the pedantic lint group.

A lint group can be added to the qsharp.json manifest as follows:

{
   "lints": [
      { "group": "pedantic", "level": "warn" }
   ]
}

[minestarks]

Why "pedantic"?

It has a slightly negative connotation, like "so picky as to be annoying". I do know Clippy uses it, but I think the name makes some sense there: they have many other groups you would want to enable before pedantic. So this is the one that's like a bunch of opinionated lints we didn't know where else to put. Even their documentation hedges it by saying "if you enable this group, expect to also use #[allow] attributes generously"

If this is our only lint group, I don't think "pedantic" makes sense.

My other problem with the name is it doesn't describe a meaningful category or purpose. As a user, how can I tell what I'm getting out of these lints by opting into them?

Do we need groups? If we do, what about more functional categories like "correctness", "style", "deprecations" etc?

[sezna]

I agree with you here, some extra color to the conversation: I think the pedantic lints in Clippy tend to be much more subjective and not as universally-accepted. I don't think the name pedantic conveys that, but maybe we can come up with a better word. Stylistic? Strict? Opinionated? I like opinionated as a group name.