title: postman sendRequest use authorization from collection
body: <p>I can send a request in a Postman pre-request script as seen below.  What I would like to do is use the same authentication as is set in the Collection so that if the Collection changes then my sendRequest follows suite.</p>
  
  <pre><code>pm.sendRequest({
      url: 'http://some_url',
      method: 'GET',
      header: {
          'content-type': 'application/json',
          'authorization': 'Basic ' + auth
      },
  
  }, function (err, res) {
      // do something
  });
  </code></pre>
  
  <p>The reason I want to do this is that I want to share the collection with partners and customers and each of them may use a different authentication type.  At the moment I have configured my collection to use basic authentication and have used variables for user name and password.  If, for example, a partner switches the collection to use OAuth then they will need to also update all of my pre-request scripts to use OAuth.</p>
  
  <p>If pm.sendRequest() was able to inherit the authentication just as each request in the collection can then the partner could make the change in one place.</p>