title: map function for objects (instead of arrays)
body: <p>I have an object:</p>
  
  <pre><code>myObject = { 'a': 1, 'b': 2, 'c': 3 }
  </code></pre>
  
  <p>I am looking for a native method, similar to <code>Array.prototype.map</code> that would be used as follows:</p>
  
  <pre><code>newObject = myObject.map(function (value, label) {
      return value * value;
  });
  
  // newObject is now { 'a': 1, 'b': 4, 'c': 9 }
  </code></pre>
  
  <p>Does JavaScript have such a <code>map</code> function for objects? (I want this for Node.JS, so I don't care about cross-browser issues.)</p>