title: extjs ajax proxy updating
body: <p>I'm started to use ExtJs4 and have question about ajax proxy. My store looks like this:</p>
  
  <pre><code>var users = new Ext.data.Store({
      model: 'User',
      autoDestroy: true,
      autoSync: true,
      autoLoad: true
      proxy: new Ext.data.HttpProxy({
          type: 'ajax',
          api: {
              create: '../users.php?action=create',
              read: '../users.php',
              update: '../users.php?action=update',
              destroy: '../users.php?action=delete'
          },
          reader: {
              type: 'json',
              root: 'users',
              idProperty: 'USRID'
          }
      }),
  });
  </code></pre>
  
  <p>when I remove some records from this store without page refreshing, it seems that all previous deleted items are stored somewhere and sended to php script on every new update. When I refresh page, first remove is ok, but any next remove again accumulate previous removed records.
  What I do wrong and how I can fix it?</p>