[docs] line numbers are copied when using linenos parameter in {% highlight html linenos %}

[GabLeRoux]

Line numbers are copied when linenos is used with highlight in documentation, copying content with the corner button.

This happens on code snippet under Markup at
http://getbootstrap.com/javascript/#tooltips

See code here
https://github.com/twbs/bootstrap/blob/master/docs/_includes/js/tooltips.html#L61-L72

I think ZeroClipboard is being used for this, so it could be an issue with the code highlighter and not bootstrap3.

Copied content:

 1 <!-- HTML to write -->
 2 <a href="#" data-toggle="tooltip" title="Some tooltip text!">Hover over me</a>
 3
 4 <!-- Generated markup by the plugin -->
 5 <div class="tooltip top" role="tooltip">
 6   <div class="tooltip-arrow"></div>
 7   <div class="tooltip-inner">
 8     Some tooltip text!
 9   </div>
10 </div>

Should be:

<!-- HTML to write -->
<a href="#" data-toggle="tooltip" title="Some tooltip text!">Hover over me</a>

<!-- Generated markup by the plugin -->
<div class="tooltip top" role="tooltip">
  <div class="tooltip-arrow"></div>
  <div class="tooltip-inner">
    Some tooltip text!
  </div>
</div>

[hnrch02]

Hmm, we don't use linenos anywhere else in the docs other than this one place. It seems that it slipped in with fd293be and hasn't been noticed ever since. @mdo Any reason you included the line numbers here?