title: Is it possible to send start and limit parameters in ajax request using Extjs 5 TreeStore?
body: <p>I've created an Ext.tree.Panel view. </p>
  
  <pre><code>Ext.define('MyApp.requests.view.QueryRequestsGridView', {
      extend: 'Ext.tree.Panel',
      useArrows: true,
      rootVisible: false,
      singleExpand: true,
      bind: {
          store: '{queryRequestsGrid}'
      },
      viewConfig:{
          markDirty: false
      },
      columns: [
          { text: 'Id', dataIndex: 'id', flex: 3},
          { xtype: 'treecolumn', text: 'Name', dataIndex: 'name', flex: 6},
          { text: 'ControlType', dataIndex: 'controlType', flex: 4, sortable: false},
          { text: 'Description', dataIndex: 'description', flex: 6}
      ],
      dockedItems: [{
              xtype: 'pagingtoolbar',
              bind: {
                  store: '{queryRequestsGrid}'
              },
              displayInfo: true
          }]
      }]
  });
  </code></pre>
  
  <p>As I can see from the docs the store of Ext.tree.Panel should be Ext.data.TreeStore.</p>
  
  <pre><code>Ext.define('MyApp.requests.model.QueryRequestsGridModel', {
      extend: 'Ext.data.TreeModel',
      fields: [
          {name: 'id'},
          {name: 'name'},
          {name: 'controlType'},
          {name: 'description'}
      ]
  });
  
  Ext.define('MyApp.requests.store.QueryRequestsGridStore', {
      extend: 'Ext.data.TreeStore',
      model: 'MyApp.requests.model.QueryRequestsGridModel',
      pageSize: 10,
      alias: 'store.queryRequestsGrid',
      root: {
          expanded: false
      },
      remoteSort: true,
      proxy: {
          startParam: 'start',
          limitParam: 'limit',
          pageParam: undefined,
          sortParam: undefined,
          noCache: false,
          type: 'ajax',
          url: 'ucis.json'
      }
  });
  </code></pre>
  
  <p>Now on view creation the TreeStore data is requested using the following url without start and limit params but with nodeParam instead:</p>
  
  <pre><code>ucis.json?node=root
  </code></pre>
  
  <p>If to replace Ext.data.TreeStore with Ext.data.Store the following url will be sent:</p>
  
  <pre><code>ucis.json?offset=0&amp;limit=10
  </code></pre>
  
  <p>The question is: does a treestore support start and limit pagingtoolbar parameters?</p>