- fix a bug where data URLs can end up with double quotes rather than single quotes

- improve handling of keyframes and font-faces (issue #17)
- better support for elements which are in iframes (issue #18)

Updated the version of the JS Beautify library bundled with the add-on (used by the Beautify option).

- added a "Beautify" button, which runs on whatever is currently in the text-box.
- added a "Refine" button, which re-reduces whatever is currently in the text-box, rather than the currently-inspected node on the page.
- fixed a bug which prevented some URLs from being fully-qualified (background-images, etc).
- fixed a bug which could result in more than one <head> or <html> element in the reduced results.

Improved handling of SVG and internally-linked content like clip-paths.