Remove heading extesions

[kazk]

Ids are handled by marked, with better implementation using unique slugs. I don't know if we need icon support, but it can be handled with overrides (#31).

marked-extensions/src/renderer.js

Lines 25 to 49 in 48abed4

	function setupHeader(renderer, options, result) {
	// heading extensions
	renderer.heading = function (text, level) {
	// you can set icons via icon::name
	const icon = text.match(/icon::([a-z-]*)/);
	let attributes = '';
	if (icon) {
	// indicate that this icon has been used
	result.icons[icon[1]] = true;
	attributes = ` class="${options.iconClassPrefix}${icon[1]}"`;
	text = text.replace(/icon::[a-z-]*/, '');
	}
	// we track headers 1 - 4 and add ids to them so that we can link to them later if we want to
	if (level < 5) {
	const header = result.headers[`h${level}`];
	const index = header.length;
	attributes += ` id="h${level}_${index}"`;
	header.push(text);
	}
	return `<h${level}${attributes}>${text}</h${level}>`;
	}
	}