title: SlickGrid multiSelect="false" does not disable keyboard multi selection
body: <p>I am using slickgrid in my project, and I want to use it's multi selection disabling option. My problem is, that the multiSelect="false" works for stopping mouse multi selection, but I can select multiple rows using SHIFT + Arrow key combination.</p>
  
  <p>Do you have any simple (built in) solution to disable arrow key multi selection too, or do I have to do it in the onSelectedRowsChanged event?</p>
  
  <p>Thank you.</p>