title: convert string timestamp to ISO 8601 compliant string
body: <p>I have a timestamp and offset in string format as shown below in two different variables:</p>
  
  <pre><code>01/14/2016 07:37:36PM
  -08:00
  </code></pre>
  
  <p>I want to convert above timestamp into <code>ISO 8601 compliant String, with milliseconds and timezone</code> so it should look like this after conversion:</p>
  
  <pre><code>2016-01-14T19:37:36-08:00
  </code></pre>
  
  <p>How can I do that? I am using jodatime library.</p>