title: AngularJS: Sorting issue
body: <p>Making use of AngularJS <code>orderBy</code> filter I've created a sortable table here,</p>
  
  <p><a href="http://plnkr.co/edit/AarOSuawXVYe9C5LBDOK?p=preview" rel="nofollow">http://plnkr.co/edit/AarOSuawXVYe9C5LBDOK?p=preview</a></p>
  
  <p>I am using the value of 'reverse' for each table header on click to determine the direction of the sort. This creates an obvious problem however as I click on different table headers they simply go to the opposite of the reverse value which may have previously been changed from another table header.</p>
  
  <pre><code>&lt;th ng-click="predicate = 'character'; reverse=!reverse"&gt;alpha&lt;/th&gt;
  &lt;th ng-click="predicate = 'num'; reverse=!reverse"&gt;num&lt;/th&gt;
  &lt;th ng-click="predicate = 'dec'; reverse=!reverse"&gt;dec&lt;/th&gt;
  &lt;th ng-click="predicate = 'value'; reverse=!reverse"&gt;&lt;/th&gt;
  &lt;th ng-click="predicate = 'date'; reverse=!reverse"&gt;date&lt;/th&gt;
  </code></pre>
  
  <p>and the ng-repeat populating my table rows using the orderBy filter</p>
  
  <pre><code>&lt;tr ng-repeat="line in infoCtrl.data | orderBy:predicate:reverse"&gt;
  </code></pre>
  
  <p>How can I isolate the scope of reverse, or give them an individual reverse value each?</p>