`cabal upload` could by default do a `sdist` and upload the thus generated tar

When I do `cabal upload`, I get
```
cabal: the 'upload' command expects at least one .tar.gz archive.
```
If no archive is given on the command line, it could first do an `sdist` and then upload the thus generated `tar.gz`.

My workaround is the following `cabal-upload` shell script:
```sh

cabal sdist | tail -1 | xargs cabal upload "$@"
cabal haddock --haddock-for-hackage | tail -1 | xargs cabal upload -d "$@"
```