title: loopback equal to date is not working
body: <p>I am new to loopback. I have a date column start_date with DATE datatype.
  when i try to fetch data with greater than or less than operations on start_date is working, but when i tried to fetch data equal to a date its not working:   </p>
  
  <p>the following is my fetching part:</p>
  
  <p>Its working:</p>
  
  <pre><code>app.models.goals.find({where: { 
      start_date: {gt:'2016-03-31'}
    }}, function(err, res) {
  });
  </code></pre>
  
  <p>Its not working:</p>
  
  <pre><code>app.models.goals.find({where: { 
      start_date: '2016-03-31'
    }}, function(err, res) {
  });
  </code></pre>
  
  <p>Data is there in DB for 2016-03-31, but empty response. Is any syntax error.please help me to solve this.</p>