Updated extension to Chrome manifest version 2

It'd be nice if you can pull this in and re-publish with Chrome.

I was also missing the https functionality, and had to hunt for a while to find this repo so I could upgrade from the published 0.4 version to 0.6 (only in your git repo).

As part of getting the unpacked version of this from git into Chrome, I had to update the manifest which necessitated a couple other minor changes. Thus my fork has a bumped version number.

-Stephen