Remove Fantomas.Extras

[nojaf]

Fantomas.Extras used to be a package that editors and FAKE scripts would use to format code. It is a thing of the past and I would like to refactor this.

Replace MAB.DotIgnore with Ignore

I would swap MAB.DotIgnore for Ignore.
The main reason is that there are some edge cases with MAB.DotIgnore and Ignore is using git status in its unit tests.

.gitignore based parser implemented in C# according to the .gitignore spec 2.29.2.

The library is tested against real git status outputs. The tests use LibGit2Sharp for that.

Move ignore code to Fantomas

I also consider moving the ignore code from Fantomas.Extras to Fantomas, as I can no longer think of a reason anybody would use that API directly.

Remove FAKEHelpers

If you want to use Fantomas from a FAKE target, the recommendation has been to use the .NET tool.
We don't encourage to use of the old FAKE helper anymore, so they should also be internalized in the Fantomas project. At a later point, we could perhaps publish a NuGet package that exposes some wrappers for the cli tool.

@baronfel does all of this make sense to you?

[baronfel]

Yep, crystal clear!