Explicit/detailed feature list in the docs

[bitprophet]

Right now there's a very basic marketing-esque blurb with some headline features (...and some that still aren't in yet >_>) on the README/homepage. And there's the tutorial, but that also (by necessity) doesn't cover more than the basics.

It'd be nice to list nearly all features somewhere, so folks can more readily tell what we've got handy without having to comb through the conceptual and/or API docs.

To some degree, this overlaps with Fabric 2's "why you want to upgrade" functionality, but I think we can safely say list everything here for new users, and say "check out this list, plus also here's some fab specific changes" on Fabric's site.