Register a one-time event listener. A little bit like jQuery’s `one`.

once.js

/**
 * Once
 * Copyright (c) 2014 marlun78
 * MIT License, https://gist.github.com/marlun78/bd0800cf5e8053ba9f83
 */

/**
 * Register a one-time event listener. Something similar to jQuery’s `one`.
 * 
 * NOTE! It doesn’t handle `target.removeEventListener(type, originalListener, useCapture)`.
 * Provides a `deregister` function instead.
 *
 * @param {EventTarget} target
 * @param {String} type
 * @param {Function} listener
 * @param {Boolean} [useCapture]
 * @returns {Function} deregister
 */
function once(target, type, listener, useCapture) {
    var capture = !!useCapture;
    target.addEventListener(type, handler, capture);

    function deregister() {
        target.removeEventListener(type, handler, capture);
    }

    function handler() {
        deregister();
        return listener.apply(this, arguments);
    }

    return deregister;
}

/**
 * Optional (and contraversal) 
 */
EventTarget.prototype.addOneTimeEventListener = function addOneTimeEventListener(type, listener, useCapture) {
    once(this, type, listener, useCapture);
};