title: Sort NSMutableArray based on strings from another NSArray
body: <p>I have an <code>NSArray</code> of strings that I want to use as my sort order:</p>
  
  <pre><code>NSArray *permissionTypes = [NSArray arrayWithObjects:@"Read", @"Write", @"Admin", nil];
  </code></pre>
  
  <p>I then have a <code>NSMutableArray</code> that may or may not have all three of those permissions types, but sometimes it will only be 2, sometimes 1, but I still want it sorted based on my <code>permissionsTypes</code> array.</p>
  
  <pre><code>NSMutableArray *order = [NSMutableArray arrayWithArray:[permissions allKeys]];
  </code></pre>
  
  <p>How can I always sort my <code>order</code> array correctly based on my using the <code>permissionTypes</code> array as a key?</p>