title: NSString to NSDate using NSDateFormatter returns null
body: <p>dateFromString returns me null when I am trying to convert NSString to NSDate
  here is my code:</p>
  
  <pre><code>    NSString *dateString = @"Wed 16 Oct 2013";
      NSDateFormatter *dateFormatter = [[NSDateFormatter alloc] init];
      [dateFormatter setLocale:[NSLocale systemLocale]];
      [dateFormatter setTimeZone:[NSTimeZone systemTimeZone]];
      [dateFormatter setDateFormat:@"EEE dd MMM yyyy"];
      [dateFormatter setFormatterBehavior:NSDateFormatterBehaviorDefault];
      NSDate *myDate = [dateFormatter dateFromString: dateString];
  </code></pre>
  
  <p>Please, give me any suggestions about this.</p>