Uploads of new packages should go to 'candidates' by default

[gbaz]

This was suggested as a change to cabal-install by @hvr but we can just change hackage-server itself to not allocate new public namespace unless a package is promoted from candidate.

This should encourage the use of the candidates feature, and more importantly vitiate against the accidental upload of internal stuff to the public hackage instance.

[hvr]

Actually, I did also suggest a change to hackage-server for namespace-allocation exactly as you describe (but maybe on a different occasion than my original cabal-install centered suggestion), since we can't easily make sure all clients are updated to the new policy (old pre-installed cabal-install clients as well as 3rd party clients such as curl-based scripts or Stack).

[gbaz]

Ok I think the change in cabal is a nicer approach, and is now done (though not in 1.24.0.0) so I'll close this in favor.

[hvr]

@gbaz fwiw, it's not enough to handle this client side; we just had another accident where a package was uploaded accidentally (ghcjs-vdom) because the tooling UI was a bit error-prone and packaged up tarballs for (still unreleased) packages that didn't belong to the user performing the upload.

[gbaz]

@hvr ok so what's the current design for this then? for gsoc we should work this out. if we just make upload url put a candidate, how do we let users force the converse? do we want to force all packages to be candidates then promoted, with no "escape hatch"?