How to add stylesets to CKEditor

richtext.js

(function($){

	var selectorMain = '.richtext,.ckeditor',
		eventNamespace = 'richtext',
		cssRootfolder = './../../css/', // Will probably change in production
		// Andi, das nachfolgende ist neu:
		stylesets = {
			standard: [
				{
					name: 'Link intern', 
					element: 'a', 
					attributes: {
						'class': 'internal'
					}
				},
				{
					name: 'Link extern', 
					element: 'a', 
					attributes: {
						'class': 'external'
					}
				}
			]
		},
		// -------
		configs = {
			standard: {
				toolbar: [{
					name: 'basicstyles',
					groups: [ 'basicstyles', 'cleanup' ],
					items: [ 
						'Bold', 
						'Italic', 
						'Underline', 
						'Strike', 
						'RemoveFormat', 
						'Styles' // NEU!!!
						]
				},{
					name: 'links',
					items: [ 'Link', 'Unlink' ]
				}],
				removeButtons: 'Underline,Subscript,Superscript',
				format_tags: 'p;h1;h2;h3;pre',
				// Andi, nachfolgende Zeile ist neu:
				stylesSet: 'standard',
				removeDialogTabs: 'image:advanced;link:advanced',
				skin: 'mascara,' + cssRootfolder + 'richtext/',
			}
		},

		richtextify = function($elem) {
			if (!window.CKEDITOR) {
				console.error('CKEditor not loaded. Aborting');
				return;
			}
			
			// Andi, das nachfolgende ist neu:
			$.each(stylesets, function (key, value) {
			  CKEDITOR.stylesSet.add(key, value);
			});
			// -------

			var elem = $elem.get(0),
				config = configs.standard,
				configName = $elem.data('richtext-config');

			if (configName && configs[configName]) {
				config = configs[configName];
			}

			CKEDITOR.replace(elem, config);
		},

		init = function() {
			$(selectorMain).each(function() {
				richtextify($(this));
			});

			$(document)
				.on(eventNamespace + ':created', selectorMain, function(e) {
					richtextify($(this));
				});

			mascara.autoinitialize(selectorMain, eventNamespace);
		};

	$(document).ready(function() {
		init();
	});
})(jQuery);