Have bots automatically sign distributable artifacts

[brson]

We sign releases manually right now, and don't sign nightlies. Would be better if the automation just did this for us.

[bheesham]

Hey @brson , is there anything I can do here?

[brson]

@bheesham Thanks for the offer but I think not. It requires access to the automation infrastructure that I'm not currently prepared to provide.

[brson]

This is done. Thanks @bheesham!

[l0kod]

Great, the signatures seems to be there but without link in the download pages.

[l0kod]

The src/etc/get-snapshot.py should use the signatures as well.