cabal: Add v2 implementation of outdated command

[erikd]

Currently the cabal outdated command only works in a directory which contains <pkg>.cabal file.

When this issue is complete:

• v1-outdated which sound work as the current version of that command.
• v2-outdated which would work where the directory it is run in has a cabal.project file.

[andreabedini]

We already have #8283

[andreabedini]

and before that we had #4831 😂

[erikd]

Closing in favor of #8283 .

[gbaz]

did you mean to reopen?

[Mikolaj]

Let's assume that was a typo. Closing.