title: Converting a string into a key->value array in PHP
body: <p>if I have a string of key->value pairs in the following format:</p>
  
  <pre><code>MIME-Version: 1.0
  From: "Tim Lincecum"
  Reply-To: "Tim Lincecum"
  Return-path: "Tim Lincecum"
  Content-Type: text/html; charset=iso-8859-1
  Subject: Giants Win World Series!
  </code></pre>
  
  <p>How do I get an array such that <code>arr['From'] = "Tim Lincecum",</code> etc</p>
  
  <p>I know there's the <code>explode()</code> function, but the only delimiter I see (colon) is in the middle of a key and a value rather than between each pair. How can I approach this?</p>