Merge branch 'patch-1' of https://github.com/mrshu/reveal.js

Gruntfile.js

 /* global module:false */
 module.exports = function(grunt) {
-
+	var port = grunt.option('port') || 8000;
 	// Project configuration
 	grunt.initConfig({
 		pkg: grunt.file.readJSON('package.json'),
@@ -78,7 +78,7 @@ module.exports = function(grunt) {
 		connect: {
 			server: {
 				options: {
-					port: 8000,
+					port: port,
 					base: '.'
 				}
 			}