[Chapter 3] Switch to "feedUrl" instead of "url"
Merge branch 'chapter-3'

Conflicts:
	app/js/feed-manager.js
[Chapter 4] Rename 'needsFeedInfo' to 'uiNeedsFeedInfo'
[Chapter 4] Use feed instance data for test instead of testing global
Merge branch 'chapter-4'
[Chapter 5] Replace magic numbers with fixture data properties
Merge branch 'chapter-5'