title: Can I include blank field in select_tag?
body: <p>Is it possible to add an option like  <code>:include_blank =&gt; 'Please Select'</code>  in a method  <code>select_tag</code>  like it is possible with the <code>select</code> method? It seems not to work. Is there any substitute for this for <code>select_tag</code> method?</p>