Integrate ACE editor

This pull request is for [task 62](https://assemblymade.com/buckets/wips/62).
It's still a work in progress; not ready to be merged yet!

TODOS:

- [ ] see if there's some way we can use commonJS requires with ACE instead
      of loading it in the global namespace
- [ ] Make it so that changes to the ace editor field actually save when you
      click the "ssve" button
- [ ] Add a test or two