Investigate - Show Valid XML Only

[michael-hawker]

Need to have a way to just show the currently valid parsed XML.

Need to walk tree and prune it for cases where the 'Trivia' indicates there's a problem...?

[michael-hawker]

Have a test branch here: https://github.com/michael-hawker/XmlSyntaxVisualizerUWP/tree/mhawker/temp-fail-remove-bad-nodes

However, I hadn't realized the XML tree was immutable, so this requires a whole different approach to process and spit back out.

[michael-hawker]

Continued a few other things atop that branch, like switching to WinUIEdit and adding unit tests, latest WIP is in https://github.com/michael-hawker/XmlSyntaxVisualizerUWP/tree/mhawker/unit-tests branch.