Release there were some issues with the way removing columns was being implemented.

So I decided to scrap that, and go for just having a hidden column style. This is what
@madshall did in his enhanced table pull request, so this is basically the hidden
column style feature form his pull request.

public/app/plugins/panel/table/editor.ts

@@ -39,6 +39,7 @@ export class TablePanelEditorCtrl {
       {text: 'Number', value: 'number'},
       {text: 'String', value: 'string'},
       {text: 'Date', value: 'date'},
+      {text: 'Hidden', value: 'hidden'}
     ];
     this.fontSizes = ['80%', '90%', '100%', '110%', '120%', '130%', '150%', '160%', '180%', '200%', '220%', '250%'];
     this.dateFormats = [