Option to upload package candidates to Hackage

[yairchu]

stack upload should have an option to upload a package candidate rather than a package.

Note that hackage doesn't generate haddocks for package candidates automatically, but one can upload them manually and it would be very useful if the upload would also do that, which can be done by

cp -r `stack path --dist-dir`/doc/html/PACKAGE PACKAGE-VERSION-docs
tar -c -v -z --format=ustar -f PACKAGE-VERSION-docs.tar.gz PACKAGE-VERSION-docs
curl -X PUT -H 'Content-Type: application/x-tar' -H 'Content-Encoding: gzip' --data-binary "@PACKAGE-VERSION-docs.tar.gz" "https://USERNAME:PASSWORD@hackage.haskell.org/package/PACKAGE-VERSION/candidate/docs"

(command based on a script by @ChrisPenner, which is for uploading docs for non-candidate packages)

[dbaynard]

Possibly one for the wishlist?

[mpilgrem]

I am closing as this feature was implemented in Stack 2.7.1.