* Preserve original quotes when rewriting CSS url() paths - important for inline SVG files which often have spaces
* Found an example in the wild with the 'charset=' part left off. This is supported by https://css-tricks.com/lodge/svg/09-svg-data-uris/ ... not sure why we aren't just testing for the 'data:' prefix here?
* Not sure why this is now coming back with a double quote after recent changes here; it's supposed to preserve the single quote from style.css??