Stuff to do in v2

[christianp]

• [x] Listen to build channels in the deep-link views, so you can select just-uploaded packages without reloading the page
• [ ] Make a clever configure-from-scratch flow for packages without a config.yml, which sets things up based on its best guess at the structure and some easy choices, like "this is one document" vs "this has lots of independent documents". At the moment you just have to set up the config in the editor with no guidance.
• [x] Put authentication on the management views, so people can't fiddle with stuff that they shouldn't!
• [x] Link to the package management from the teacher launch.
• [ ] Limit dynamic registration in some way
• [ ] Support themes somehow!
• [x] Offer GitHub/version control integration through a webhook
• [x] Offer a public build tool not accessed through LTI