title: draw only top, right, and bottom border around a uilabel
body: <p>i try to add border for a uilabel, but i only want to have <code>top, right, and bottom</code> border. </p>
  
  <p>like this </p>
  
  <pre><code>           ----------------
                            |
              I am a label  |
                            |
             ----------------
  </code></pre>
  
  <p>I try to use these codes, but it adds all 4 sides by default</p>
  
  <pre><code>    myLabel.layer.borderWidth = 1;
      myLabel.layer.borderColor = [UIColor blackColor];
  </code></pre>
  
  <p>Is that anyway i can only add 3 sides, or even 1 or 2 sides?</p>
  
  <p>Thanks!</p>