title: C++11 Chrono - How to cast 'unsigned int' to a time_point<system_clock>?
body: <p>I have a function that has this signature:</p>
  
  <pre><code>void checkTime (const std::chrono::time_point&lt;std::chrono::system_clock&gt; &amp;time)
  {
     //do stuff...
  }
  </code></pre>
  
  <p>I need to call the above function like this:</p>
  
  <pre><code>void wait_some_time (unsigned int ms)
  {
      //do stuff...
      checkTime(ms); //ERROR: How can I cast unsigned int to a time_point&lt;system_clock&gt; as now() + some milliseconds?
      //do more stuff...
  }
  </code></pre>
  
  <p>I want to use like this: </p>
  
  <pre><code>wait_some_time(200); //wait now + 200ms 
  </code></pre>
  
  <p><strong>Question:</strong></p>
  
  <p><strong>How can I cast 'unsigned int' to a const std::chrono::time_point that has the milliseconds value ?</strong></p>
  
  <p>Thanks!</p>