Fix mixed content errors loading images/css/js

When this page is opened over https Chrome refuses to fetch external resources over http (i.e. unencrypted). These changes use protocol-relative URLs, so that external resources are fetched over the same protocol as the page itself.

I've also made the external href to Google Code https.
Merge pull request #4 from moreati/patch-1

Fix mixed content errors loading images/css/js