title: How to add timestamp directly to the cell that I just filled/edited in google sheet
body: <p>I would like to ask that is it possible to add the timestamp directly to all the cells that I just filled/edited in google sheet. For example, I just added some contents to the cell A1, like: Hello, then what I expect displaying in the cell A1 is something like: Hello - 20.05.2016 00:50.</p>
  
  <p>Are there having some ideas? :D</p>
  
  <p>Thank you</p>