DONE:
+ Implemented HtmlNode class. (A modification of Upp::XmlNode class)
+ Implemented TidyHtmlParser, TidyHtmlParser::Node classes for traversing the document tree.
+ Implemented ParseHtml and RepairHtml convenience functions.
+ Added a minimal code example, parsing the legacy example.com.

TODO:
- Enable U++'s memory managers in libtidy.
- Add U++ callbacks for libtidy's message queue.
- Refactor buffer allocation code.
- Add Topic++ documentation.
- Add more example code (both console & gui).
- Test the Windows build.
- Cosmetics.

#include <Core/Core.h>
#include <Core/SSL/SSL.h>
#include <HtmlTools/HtmlTools.h>

using namespace Upp;

void PrintHtml(const HtmlNode& node)
{
	for(const HtmlNode& q : node) {
		if(q.IsTag("title"))
			Cout() << q.GatherText();
		else
		if(q.IsTag("p"))
			Cout() << q.GatherText();
		else
		if(q.IsTag("a"))
			Cout() << "For more information, see: " << q.Attr(0) << EOL;
		PrintHtml(q);
	}
}

CONSOLE_APP_MAIN
{
	StdLogSetup(LOG_FILE);
	HtmlNode n = ParseHtml(
		HttpRequest("https://example.com/").Execute(),
		{ { "wrap", 96 } }); // libtidy options...
	PrintHtml(n);
}

+ U++'s memory managers are enabled.
+ TidyHtmlParser::Node class gained ToHtmlNode() method. Allows any node to be converted to HtmlNode class.
+ Package is also uploaded to upp-components repo.