Use an optimised one-shot DOM analyser for CSS

[hrj]

Currently jStyleParser has two types of analysers:

• A DirectAnalyser which accepts a single element, and returns NodeData for that element.
• Analyser.evaluateDOM which processes the whole DOM and creates a gigantic Map[Element, NodeData].

A third approach can be considered, where the Analyser.evaluateDOM traverses the tree and invokes a callback function for every element, passing it the NodeData. The callback function can then store the NodeData or the computed styles into the element.

Needs further thought.