Enable passing options for parsing Markdown.

Closes #1163, #1495.

test/test-markdown-options.js

@@ -0,0 +1,26 @@
+Reveal.addEventListener( 'ready', function() {
+
+	QUnit.module( 'Markdown' );
+
+	test( 'Options are set', function() {
+		strictEqual( marked.defaults.smartypants, true );
+	});
+
+	test( 'Smart quotes are activated', function() {
+		var text = document.querySelector( '.reveal .slides>section>p' ).textContent;
+
+		strictEqual( /['"]/.test( text ), false );
+		strictEqual( /[“”‘’]/.test( text ), true );
+	});
+
+} );
+
+Reveal.initialize({
+	dependencies: [
+		{ src: '../plugin/markdown/marked.js' },
+		{ src: '../plugin/markdown/markdown.js' },
+	],
+	markdown: {
+		smartypants: true
+	}
+});