title: MongoDB: Check if value is null or the array is empty
body: <p>I would like to match all documents that don't contain the "Company" attribute or where the "Company" value is null or an empty array.</p>
  
  <pre><code>User.find({Company: {$in: [null, [] ]}}, function (err, users) {
        if (err) { throw err; }
        console.log(users.length);
  
  }).then(function(doc) {
        console.log("finish User Company");
  });
  </code></pre>