Refactor Page Layout and Notebook Content

[sameersingh]

Page layout should be separate from the HTML that contains the notebook render.

The page layout should be a Play template that has a div for the notebook contents, and then calls one of the Moro views (currently, static, present or wolfe). The Moro view should insert the html into the div with the given id.

Page layout is something users will modify heavily, while Moro view are quite stable (configurable via CSS).

[sameersingh]

259741378c4f38147da5f5b4d9c217c4b4b6ebd8 and 6173c3918dfed4ecf92f231c5baa5de7e7e29a81 go a long way in achieving this:

• staticContent and staticImports control generic notebook code
• layout and formatting controlled on the outside, e.g. wolfe, demo, static, statnlpbook, etc.

Main TODOs:

• ACE theme is not configurable, making scala cells look ugly in wolfe, and vice versa. Best way to achieve this is by allowing ONLY ACE editors, and the theme is a parameter to staticContent. See #48.
• In general, separate Scala and Wolfe cells don't make sense. See #49.

[sameersingh]

48 and #49 closed, so this is done as well.