config option for disabling the help overlay

js/reveal.js

@@ -85,6 +85,10 @@
 			// i.e. contained within a limited portion of the screen
 			embedded: false,
 
+			// Flags if we should show a help overlay when the questionmark
+			// key is pressed
+			help: true,
+
 			// Number of milliseconds between automatically proceeding to the
 			// next slide, disabled when set to 0, this value can be overwritten
 			// by using a data-autoslide attribute on your slides
@@ -1278,6 +1282,8 @@
 	 */
 	function showHelp() {
 
+		if( config.help ) {
+
 			closeOverlay();
 
 			dom.overlay = document.createElement( 'div' );
@@ -1314,6 +1320,8 @@
 
 		}
 
+	}
+
 	/**
 	 * Closes any currently open overlay.
 	 */