Add scalafix rules for 0.4.x -> 0.5.x

[CJSmith-0141]

Take three haha

[bpholt]

@CJSmith-0141 I'm going to merge this and then follow up with some tweaks to the build definition—it looks like the scalafix artifacts are not being published from CI with the separate build.sbt. I don't think there's a reason that needs to be separate, though, so I'll just combine those pieces into the main build.

Are you working on the additional Scalafix cases? If not, I'll take a look.

[CJSmith-0141]

@CJSmith-0141 I'm going to merge this and then follow up with some tweaks to the build definition—it looks like the scalafix artifacts are not being published from CI with the separate build.sbt. I don't think there's a reason that needs to be separate, though, so I'll just combine those pieces into the main build.

Are you working on the additional Scalafix cases? If not, I'll take a look.

I was giving it a shot but couldn't get the index based calls and the argument named calls to refactor in the same pass correctly. Would be easier to patch the patch but I don't know if that's doable or advisable.