Implement worksheets list (using Angular)

- Added support to create worksheets through the bundle service with new /api/worksheets [post] api.
- Added support to create worksheets from the web UI.
- Transitioned worksheets list to use AngularJS.
- Added new /api/worksheets/ingo [get] API to provide templating information abck to AngularJS.
- Added support for worksheet keyboard shortcuts (up/down for navigation and ctrl+up/ctrl+down for insertion).
- Added animations to the worksheets list.

![angularworksheetlist](https://cloud.githubusercontent.com/assets/3478847/2674721/5b0fc0b8-c107-11e3-9710-ba2f93a0e590.png)