title: How can I add paging to my store with loads data from the server via proxy?
body: <p>I'm using this store:</p>
  
  <pre><code>Ext.define('newStore', {
    extend: 'Ext.data.Store',
    model: 'myModel',
    pageSize: 5,
    proxy: {
      type: 'ajax',
      url: '/myJson.json',
      reader: {
        type: 'json',
        root: 'myThings',
        totalProperty: 'total'
      }
    }
  });
  </code></pre>
  
  <p>And I'm using this pager:</p>
  
  <pre><code>  { 
      xtype: 'pagingtoolbar',
      store: 'newStore'
    }
  </code></pre>
  
  <p>The json:</p>
  
  <pre><code>{"total": 10, "success": true, "myThings": [{"thingNum": 1},{"thingNum": 2},{"thingNum": 3},{"thingNum": 4},{"thingNum": 5},{"thingNum": 6},{"thingNum": 7},{"thingNum": 8},{"thingNum": 9},{"thingNum": 10}]}  
  </code></pre>
  
  <p>The problem is my store just loads all <code>myThings</code> into the grid even though my <code>pagingtoolbar</code> has 1-5 with total 10.</p>
  
  <p>How can I get my grid to properly page?</p>