Add hash-based routing/state management

The current Openbibl bibliography viewer page has no means of preserving the state of the page, e.g., to snapshot the currently selected index or search terms. Implementing a url-based routing scheme would allow the current state of the application to be captured, which would facilitate bookmarking or sharing.

Examples of url (hash) based routing are found in and as add-ons for most JS frameworks:

http://angular-ui.github.io/ui-router/site/#/api/ui.router
http://documentcloud.github.io/backbone/#Router
http://emberjs.com/guides/routing/specifying-the-location-api/

See an example of the URL reflecting the state of discovery at the Blacklight demo:

http://demo.projectblacklight.org/