Downloaded packages clutter up the zopen directory

[AnthonyGiorgio]

After using zopen for a while, the downloaded packages tarballs start to clutter up the filesystem. It would be nice if these could live in a separate downloads directory. They could also be removed at some point when a tarball is no longer useful.

[MikeFultonDev]

@AnthonyGiorgio i think this is better now. Please re-open if you think there are still UX issues here.