function registerEasing(args) {
    var name = args[0],
        callback = args[1];
    if (!isString(name)) {
        console.warn("VelocityJS: Trying to set 'registerEasing' name to an invalid value:", name);
    } else if (!isFunction(callback)) {
        console.warn("VelocityJS: Trying to set 'registerEasing' callback to an invalid value:", name, callback);
    } else if (Easings[name]) {
        console.warn("VelocityJS: Trying to override 'registerEasing' callback", name);
    } else {
        Easings[name] = callback;
    }
}
Used to register a easing. This should never be called by users
directly, instead it should be called via an action:<br/>
<code>Velocity("registerEasing", "name", VelocityEasingFn);</code>