title: How to get date of one day before in extjs field
body: <p>I have the following date field i want to get date of one day before , how can i get that ? 
  In my form panel</p>
  
  <pre><code> items: [{
      fieldLabel: 'Start Date',
      name: 'fromdate',
      ref: '../fromdate',
      id: 'fromdate',
      vtype: 'daterange',
      value: new Date(),
      endDateField: 'todate' // id of the end date field
  }, {
      fieldLabel: 'End Date',
      name: 'todate',
      id: 'todate',
      vtype: 'daterange',
      value: new Date(),
      startDateField: 'fromdate' // id of the start date field
  }]
  </code></pre>
  
  <p>Today I am getting 03/23/2011 but I want 03/22/2011 How I can get 03/22/2011? </p>