Make HTML5 shiv a local resource

Including the HTML5 shiv directly from googlecode.com is considered bad practice:

1) It causes an additional DNS lookup
2) The ressource from SVN is not cacheable and not served compressed.

see: http://zoompf.com/blog/2012/05/html5shiv-and-serving-content-from-code-repositories
Merge pull request #180 from fhemberger/html5shiv

Performance: Make HTML5 shiv a local resource