Get rid of old modal types

Fixes TryGhost/Ghost-UI/issues/17
Merge pull request #2401 from JohnONolan/fix-modal

Get rid of old modal types
Watch changes in Ghost-UI

refs TryGhost/Ghost-UI#18
- Add bower_components/ghost-ui to grunt watch
Merge pull request #2402 from halfdan/watch-ghost-ui

Watch changes in Ghost-UI
Refactor the Ghost Editor

issue #2385, issue #2108

- Separate out the various objects which form the editor into their own
  modules
- Decouple the modules where possible
- Rename and reshuffle bits of modules for consistency
- Minimise public APIs of the modules, and ensure they are consistent
- Add comments to the modules