Load fonts over SSL if Subway is on SSL, otherwise they won't load

Chrome: [blocked] The page at 'https://foo/' was loaded over HTTPS, but ran insecure content from 'http://fonts.googleapis.com/css?family=Open+Sans:400italic,400,300,600,700,800': this content should also be loaded over HTTPS.
Merge pull request #325 from cjb/fix-font-load

Load fonts over SSL; otherwise they won't load when Subway is on SSL