title: UiTextView with edge to edge exclusion path cause all the text to disappear
body: <p>I have a <code>UITextView</code> and i want to add a custom <code>UIView</code> to it and make the text flow above and below like so:</p>
  
  <pre><code>+----------------+
  |------txt-------|
  |                |
  |     UIView     |   
  |                |
  |------txt-------|
  |----------------|
  |----------------|
  +----------------+
  </code></pre>
  
  <p>I tried to achieve this by adding an exclusion path that has the <code>UITextView</code> width and the <code>UIView</code>'s height like so:</p>
  
  <pre><code>CGRect exclusionFrame=CGRectMake(0, 
                                  CGRectGetMinY(element.frame),
                                  self.textView.textContainer.size.width,
                                  CGRectGetHeight(element.frame)); 
  self.textView.textContainer.exclusionPaths=@[[UIBezierPath bezierPathWithRect:exclusionFrame]];
  </code></pre>
  
  <p>But for some reason if the exclusion path's width equal the textView's width all the text below the <code>UIView</code>  (aka <code>element</code>) disappear. When i reduce the exclusion path's width by one the text appear with a one letter column next to the <code>UiView</code> like this:</p>
  
  <pre><code>+----------------+
  |------txt-------|
  |a               |
  |d     UIView    |   
  |e               |
  |------txt-------|
  |----------------|
  |----------------|
  +----------------+
  </code></pre>
  
  <p>Why can't i create a edge to edge exclusion path and is there a way around this predicament? </p>