Capture element state and reuse it

[sylvainhalle]

Implement function that compares the same element in two different snapshots (or states) of a page.

Discussion points

• The original function in Cornipickle worked because each DOM element touched by the interpreter was given an ID. If the element moved inside the structure of the page, one could still track it because of this ID (even if its DOM path changed). Can we do this with the current setup?
• An alternate way of doing this would be to create a JS object that captures all the relevant properties of the DOM node, so that its track inside the document afterwards does not need to be kept.

[sylvainhalle]

Suggestion: take two snapshots and evaluate the property by comparing the two