First draft color picker

Summary: This implements a first draft version of colorpicker for structured blocks. I don't like how it works, but it works :P. We can probably use it as a stopgap for a while

Test Plan:
View demo
- Add fill
- Change fill color
- reload see that colors are still right

Reviewers: john, pamela

Subscribers: #cs

Differential Revision: http://phabricator.khanacademy.org/D14620
Re-work colorPicker to use new Structured blocks color model.
Merge with master.
Update structured-blocks.
Move tooltipEngine stub.
Add in support for the number scrubber.
Update structured-blocks.
Merge branch 'arcpatch-D14620'
Improve demo quality on the iPad, prevent scrolling. Update structured-blocks.
Put i18n.js in core_deps instead of in shared

Summary:
live-editor's shared is loaded in webapp, where i18n.js will already exist.
I think this belongs in core_deps, which isn't loaded in webapp, alongside
jquery and friends.

It's interesting to note that i18n.js in live-editor has both the contents of
i18n.js from webapp, and also handlebars helpers defined in
javascript/shared-package/handlebars-extras.js to do with i18n things.

Test Plan: Not sure what the procedure is here

Reviewers: pamela, john

Reviewed By: john

Subscribers: alexrodrigues, #cs

Differential Revision: http://phabricator.khanacademy.org/D14628
Update structured-blocks.
Merge branch 'master' of github.com:Khan/live-editor