title: Context menu to add column not working when defining columns property to hide some columns
body: <p>I needed a way to create a spreadsheet where user can potentially paste in any no of columns. Currently pasting things in the spreadsheet does not work as mentioned here <a href="https://github.com/warpech/jquery-handsontable/issues/553" rel="nofollow">https://github.com/warpech/jquery-handsontable/issues/553</a>, so I wanted to enable the context menu to add column. This works fine when you have plain array as data source and you are not setting the columns property, but if you do need to define the columns attribute then things dont work when setting the </p>
  
  <pre><code>contextMenu: ['col_right']
  </code></pre>
  
  <p>. I needed to define the columns property because I need to hide certain columns (as mentioned here <a href="https://github.com/warpech/jquery-handsontable/issues/120" rel="nofollow">https://github.com/warpech/jquery-handsontable/issues/120</a>).
  The only way to make things work would be to define custom action for context menu, but I am not sure how to go about it.</p>
  
  <p>Here is a jsbin : <a href="http://jsfiddle.net/8V4Z5/1/" rel="nofollow">http://jsfiddle.net/8V4Z5/1/</a></p>
  
  <p>Thanks</p>