Adds clean task to remove unnecessary dirs in /out
Added web components revolution presentation
Add @addyosmani's "yo polymer" talk #30
Add @varunkumar's talk #30
Add @markdalgleish's talk #30
Source formatting #55
Merge branch 'pr-55'

Conflicts:
	docpad.js
Open external links in new tabs
Articles card parses/includes unrelated content - Fixes #58
Open external links in a different tab
Additional styles for single layout
Add marcy's article on a11y in shadow dom