add featured quote to story

[techieshark]

the story full body view should include the full body and the featured quote (as a blockquote, after 2nd paragragh) - see #73 for style

Forked this issue off of #74

• [x] add quote to API output
• [x] add quote to FullStory type
• [x] add quote to json decoder in Data.elm
• [x] add quote to frontend

[techieshark]

Fixed by PR #80