Trim trailing spaces and convert tabs to spaces.
Remove unused images.
Add img alt text and dimensions.
Be consistent with indentation.

Use 2 spaces.
Add Respond.js v1.4.1.
Losslessly compress osscdn-logo.png.

Before: 18520 bytes
After:  11712 bytes
Add frontend/app/data to .gitignore.
Make the browser prompt show in IE < 9.
Update html5-boilerplate to the latest git.

Remove unused html5 boilerplate files, unused classes and the Google Analytics snippet.
Use the minified JS files.
Add meta keywords and description.