title: explode string if it contains non-alpha characters
body: <p>How can I explode a string like <code>"bla_bla"</code> into an array like <code>array('bla', 'bla')</code>?</p>
  
  <p>The delimited <code>_</code> can also be any character besides numbers 0-9 and letters A-Z (both upper and lower case).</p>