Revert "Fix #1131 : Add windows Ctrl+C handling"

[aryairani]

Revert #1611 due to macOS build regression / interaction with haskell/cabal#4739

[sharno]

Instead of reverting, isn't this better handled with -optP-Wno-nonportable-include-path?
Seems that it'll succeed if we just silence this error.

example:
PostgREST/postgrest#1332

[aryairani]

@sharno Maybe — I'm not sure I want to revert either:

What I'd like to do is go back in time to undo the merge and its effect on the git history, put better CI in place, and then try going forward again from there, including possibly the -optP-Wno-nonportable-include-path route or some other.

Unfortunately, undoing the effect on the git history isn't possible, as others have already pulled the failing master branch, so I believe reverting is still the best option for now. Then we can try to recreate your PR in a way that passes the updated CI.

So now I'm just waiting to confirm that https://travis-ci.org/github/unisonweb/unison/builds/699385107 ("updated CI") fails as expected, and then merge this.