title: Getting the substring from a certain character in NSString
body: <p>If I have an NSString that is initially:</p>
  
  <pre><code>"ABCDE*FGHI"
  </code></pre>
  
  <p>How do I make it turn into </p>
  
  <pre><code>"FGHI"
  </code></pre>
  
  <p>In other words, everything from the asterisk onwards is kept.</p>
  
  <p>Likewise, how would I turn it into:</p>
  
  <pre><code>"ABCDE"
  </code></pre>
  
  <p>(everything up to the asterisk is kept)</p>
  
  <p>Thanks</p>