Re-indent ratchicons.scss and use single quotes.
Auto-generate Ratchicons data to be used by Jekyll.

Backported from Bootstrap, adapted for Ratchet.
Run `grunt`.
Add "grunt/*.js" in the JSHint and JSCS checks.
Work around https://github.com/jekyll/jekyll/issues/1801
Merge pull request #453 from twbs/ratchicons

Auto-generate Ratchicons