Retain [some?] non-style attributes about visual-html

[DylanPiercey]

@vwong this tool actually does preserve a list of attributes deemed to be visual (https://github.com/eBay/visual-html/blob/master/src/html-properties.ts#L1). I'm not quite sure why img src didn't make the list, I think that should be added.

As far as alt text and aria attributes I feel it belongs in another tool. I've thought since building this that a sister tool for snapshotting and normalizing the a11y tree would be great. Eg it should normalize <label>, aria-label etc. I've wanted to build this "audible-html" for a while but just haven't had the time.

[vwong]

audible-html sounds like an even better idea! I might be keen to try building that myself, using this repo as a starting point.

But for now <img src> wasn't preserved in my testing, though the applied styles were.