Better About Box

[sraboy]

There's a simple one in there but it's been disabled. I'd like a tabbed one with tabs like this:

1. General information, copyright
2. Readme
3. License Information
   (maybe) 4. Changelog

The Readme, License and Changelog should use https://github.com/ArthurHub/HTML-Renderer, which supports Markdown, so we can just use the same docs from the repo. See Cyotek's ImageBox demo app for an example of using the control with Markdown.