title: php removing excess whitespace
body: <p>I'm trying to remove excess whitespace from a string like this:</p>
  
  <blockquote>
    <p>hello &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; world</p>
  </blockquote>
  
  <p>to</p>
  
  <blockquote>
    <p>hello world</p>
  </blockquote>
  
  <p>Anyone has any idea how to do that in PHP?</p>