title: Apache Commons CLI - option type and default value
body: <p>How can I give a CLI Option a type - such as <code>int</code> or <code>Integer</code>? (Later, how can I get the parsed value with a single function call?)</p>
  
  <p>How can I give a CLI Option a default value? Such that <code>CommandLine.getOptionValue()</code> or the function call mentioned above return that value unless one is specified on the command line?</p>