Embedding Interface

[doolittle]

We want users to embed notebooks on their own blogs. This interface will allow them to do so via a copy-and-paste script tag and provide instructions for common platforms (i.e. tumblr, jekyll, wordpress).

The interface will be accessible through a new "share" button in the toolbar.

The interface will allow users to turn on or off the notebook title, which will give us the framework for passing more embed configuration options in the future.

Design forthcoming.