title: Mongoose delete by timestamp
body: <p>I have my mongoose model:</p>
  
  <pre><code>LogSchema = new Schema({
      level : String,
      code: String,
      message: String,
      Timestamp : { 
        type : Date, 
        default: Date.now 
      }
  })
  </code></pre>
  
  <p>I'm trying to delete all documents older than 30 days (Timestamp field) using this code:</p>
  
  <pre><code>var d = new Date();
  var older_than = new Date(d.setDate(d.getDate() - 30));
  Log.remove({ Timestamp : {$lte : older_than } }, function(err) {
      if (!err) {
          console.log("Clean complete")
      } else {
          console.log("Clean error")
      }
  });
  </code></pre>
  
  <p>I see on console: "Clean complete", but I still have all documents older than 30 days.</p>
  
  <p>Something wrong in my code?</p>