Updates modernizr custom build

Updates modernizr custom build to include html5-shiv and include all
core features used on the site. Custom build URL:
http://modernizr.com/download/#-fontface-backgroundsize-borderradius-box
shadow-opacity-rgba-textshadow-generatedcontent-cssgradients-input-input
types-geolocation-touch-printshiv-cssclasses-addtest-teststyles-testprop
-testallprops-prefixes-domprefixes-load

Performs minor code cleanup (trailing return, remove unused comment,
remove unused script).