title: Set Default Value in Dropdownlist based on current date
body: <p>If I have a dropdownlist like so:</p>
  
  <pre><code>&lt;select id="dropdown"&gt;
      &lt;option value="2017-01-01T00:00:00"&gt;January 2017&lt;/option&gt;
      &lt;option value="2017-02-01T00:00:00"&gt;February 2017&lt;/option&gt;
      &lt;option value="2017-03-01T00:00:00"&gt;March 2017&lt;/option&gt;
      &lt;option value="2017-04-01T00:00:00"&gt;April 2017&lt;/option&gt;
      &lt;option value="2017-05-01T00:00:00"&gt;May 2017&lt;/option&gt;
      &lt;option value="2017-06-01T00:00:00"&gt;June 2017&lt;/option&gt;
      &lt;option value="2017-07-01T00:00:00"&gt;July 2017&lt;/option&gt;
      &lt;option value="2017-08-01T00:00:00"&gt;August 2017&lt;/option&gt;
      &lt;option value="2017-09-01T00:00:00"&gt;September 2017&lt;/option&gt;
      &lt;option value="2017-10-01T00:00:00"&gt;October 2017&lt;/option&gt;
      &lt;option value="2017-11-01T00:00:00"&gt;November 2017&lt;/option&gt;
      &lt;option value="2017-12-01T00:00:00"&gt;December 2017&lt;/option&gt;
      &lt;option value="2018-01-01T00:00:00"&gt;January 2018&lt;/option&gt;
      &lt;option value="2018-02-01T00:00:00"&gt;February 2018&lt;/option&gt;
      &lt;option value="2018-03-01T00:00:00"&gt;March 2018&lt;/option&gt;
      &lt;option value="2018-04-01T00:00:00"&gt;April 2018&lt;/option&gt;
      &lt;option value="2018-05-01T00:00:00"&gt;May 2018&lt;/option&gt;
      &lt;option value="2018-06-01T00:00:00"&gt;June 2018&lt;/option&gt;
      &lt;option value="2018-07-01T00:00:00"&gt;July 2018&lt;/option&gt;
  &lt;/select&gt;
  </code></pre>
  
  <p>How do I set the default value to equal today's current month-year via js?</p>