title: Change excel date format from slash to dot
body: <p>In my excel file I have lot of data and there is one column with date formatted as 23/05/2015 as example. Now I want to change all the date as formatted like 23.05.2015. That is changing the date format from slash to dot.</p>
  
  <p>As I said the file contains some thousands of rows. I don't want to go through all the rows and change it manually. Is there any easy way to do this? </p>