Add support for AMD modules (Require.js)

[mvasilkov]

Because compatibility.

Something along these lines would do:

(function (root, factory) {
    if (typeof define === 'function' && define.amd) {
        // AMD. Register as an anonymous module.
        define([], factory);
    } else if (typeof module === 'object' && module.exports) {
        // Node.
        module.exports = factory();
    } else {
        // Browser globals (root is window)
        root.noop = factory();
  }
}(this, function () {
    // Return a value to define the module export.
    return function noop(){};
}));