Add ImportLookup

[lue-bird]

Implementing a lookup that helps figure out the module-local qualification for things https://github.com/jfmengels/elm-review-simplify/pull/82#discussion_r1096590841

• [x] collect module imports
• [x] collect enough info to know whether a variant is exposed with Type(..)
• [x] CheckInfo etc.
• [x] Collection etc.
• [x] correct existing fixes. There's a lot of code replacing to a value or function, so correcting was a bit of a pain but it's done so it's done. (complete including Just, Nothing, Err, Ok, True, False). If you find other ones, let me know!
• [x] cover implicit default imports
• [x] merge imports

Overall, this is great because you can be sure that fixes (like those of #82) will always produce valid code. (well except when a module has a member with the same name as an implicitly imported thing)

[lue-bird]

I hope existing code doesn't break since we now use Rule.withContextFromImportedModules (I don't think it changes the way the rule is run here but you know best).

[jfmengels]

I hope existing code doesn't break since we now use Rule.withContextFromImportedModules (I don't think it changes the way the rule is run here but you know best).

It won't in this case. That can only change the ProjectContext given to fromProjectToModule, where the previous context's fields were ignored anyway.

[jfmengels]

I'll merge this now, we can tackle the other comments later. Great work @lue-bird :heart: