Add list of top 10 most downloaded non-core packages/themes

This is a continuation of atom/atom#7251. Could you replace the featured packages/themes list with lists of the top 10 most downloaded non-core packages and themes?

Why replace? Why not in addition to the featured packages / themes list? One of the nice things (in principle anyway, I know it hasn't been updated often) about having featured packages is that we can feature packages that might otherwise not be easily found (ie. packages that wouldn't make the top 10 most downloaded list).

@mnquintana Sure, you make a good point about being able to feature non-popular packages.

"featured" packages are waay too stale, the list hardly change! i think it needs more love, a better algorithm to give interesting new packages a chance (based on downloads/stars/installs or even other criterias), hide already installed ones, hide whatever the user thinks not interesting. I'm not a data geek, but if I were I would have so much fun with this :D

also caching the list on a regular interval (very relaxed like 30 min or so) to be ready on settings load might be a good idea

I'd love a top ten area. Or just a way to view all and sort by usage on the main site.

ah, for future folks, you can, it's just a little hard to find: https://atom.io/themes/list?direction=desc&sort=stars