Fixes notes and citations displayed on bibliography page.

Quotes were being treated as instructions and removed. Show page now
uses the scopes to differentiate between notes and citations.
Improves rendering of book details.

Adds new Citations helper (and tests).
Fixes two feature spec.

Notes titles are rendered as a block of HTML now, rather than a simple
string so the selector was not finding the plaintext. But they were only
failing on Travis CI.
Fixes two minor issues with Citations rendering and styling.