fixing mixed content errors: fonts.googleapis.com
fixing mixed content errors: leaflet.js

cdn.leafletjs.com can be replaced with https://d591zijq8zntj.cloudfront.net

according to this rule in HTTPS-Everywhere:

https://github.com/EFForg/https-everywhere/blob/master/src/chrome/content/rules/Leaflet_JS.com.xml
Merge pull request #223 from yardenac/mixed

Fix some mixed content issues