title: jqgrid edit and add rows with "tab" key
body: <p>I'm new to jqgrid , and I'm trying to navigate through the grid with "tab" key.
  I want to be able to edit a row, and when I'm editing the last cell in that row, if I click the tab key it will save the current row changes (in the client side , and not by clicking enter) and set the focus to the next row and edit it's cells , and when I get to the last row and cell, the tab click will add a new row and make it in edit mode. </p>
  
  <p>I tried with in line editing and then with cell editing but always got stuck...
  how can this be done? </p>
  
  <p>Thanks in advance.</p>