[Help-nano] Language-specific replacement for `formatter`

[Anthony Sottile]

Hi! I've noticed that `formatter` has been removed in nano 3.x,
however I've previously found it pretty useful for running things like
`go fmt` (or sorting for gitignore for example).

Whether I had a formatter or linter I could run ^T and it would
usually do what I want.  With the removal of `formatter` from nanorc
is there a way to restore that behaviour?

Here's an example of a nanorc where I use a formatter (yes the irony
is not lost on me):
https://github.com/asottile/scratch/blob/3d0eaad63e38761ed2217565e0cd23f3af67966c/nanorc/gitignore.nanorc#L3

Additionally (not committed) I have this for go:

formatter gofmt -w

I work on a _ton_ of different file types (20+) so setting up a
shortcut for each formatter for each language is really not feasible.
I'd be sad to see this feature removed permanently

(maybe this is an email asking for restoration of `formatter`)

Thanks!

Anthony