title: Angular: further dynamic filtering issue
body: <p>I'm trying to get these dynamic filters working and its almost there I think.  Looks like the model isn't being passed back to the watch function.  I would've expected it to work with the first set of filters at least but it doesn't.</p>
  
  <p>What I'm trying to achieve is that when the user selects an option from the select list and sets a value in the input box the data is filtered.  The user can optionally add another set of filters by clicking the "add fields" button.  If there user completes the second set of filters then the data is filtered further.</p>
  
  <p><a href="http://plnkr.co/edit/oSjchluEX54oJ9rvfNS9?p=preview" rel="nofollow">This</a> is what I've got so far.  If there's only one filter showing then shouldn't it just work?</p>
  
  <p>This is the code that creates the user defined filters.</p>
  
  <pre><code>&lt;div data-ng-repeat="filter in filters"&gt;
    &lt;select ng-model="filter.id"&gt;
      &lt;option value="age"&gt;Age&lt;/option&gt;
      &lt;option value="customerId"&gt;CustomerID&lt;/option&gt;
      &lt;option value="productId"&gt;ProductID&lt;/option&gt;
      &lt;option value="name"&gt;Name&lt;/option&gt;
    &lt;/select&gt;
    &lt;input type="text" ng-model="data.search[filter.id]"&gt;
    &lt;button class="remove" ng-show="$last" ng-click="removeFilter()"&gt;-&lt;/button&gt;
  </code></pre>
  
  <p>
     Add fields</p>
  
  <p>I think I'm almost there, got a better understanding of hierarchical scope.  I've referred to a few tutorial and examples but I'm not quite there yet.  I think my issue with this is that I'm not communicating the models properly.  Still a little bit lost with this.  Any further tips/suggestions would be great.  I'm wondering if I should move some of he code from the controller in my directive into the <code>resultsCtrl</code> controller.  Really not sure.</p>
  
  <p>This <a href="http://jsfiddle.net/mrajcok/7MhLd/" rel="nofollow">fiddle</a> gave me the idea to use <code>filter.id</code> within my template <code>ng-repeat</code></p>
  
  <p>This <a href="http://plnkr.co/edit/A29hl6?p=preview" rel="nofollow">plnkr</a> was helpful.</p>
  
  <p>I'm getting somewhere now.  <a href="http://plnkr.co/edit/kXBjiqYBN4ymg0AuNtX4?p=preview" rel="nofollow">This plnkr</a> shows it working, the last thing I want to do with it is when you remove a filter it automatically updates the search object to remove the relevant filter.</p>
  
  <p>Any suggestions on how to do this?</p>