Port to Firefox Mobile (Fennec+Electrolysis)

Both Torbutton and HTTPSEverywhere are going to have some fun times dealing with something the Fennec people call 'Electrolysis': https://bugzilla.mozilla.org/show_bug.cgi?id=629820

It prevents components and observers from getting events originating in different tabs. You must register your observers in each process manually: https://wiki.mozilla.org/Mobile/Fennec/Extensions/Electrolysis

I've decided to port HTTPSEverywhere to Fennec first because it will be easier and more straight-forward to doing Torbutton.