Issue #291 export only visible columns

smash/web/static/js/smash.js

@@ -392,6 +392,7 @@ function createTable(params) {
             buttons: [
                 { extend: 'excel', 
                   exportOptions: {
+                    columns: ':visible',
                     modifier: { page: 'all', search: 'applied', order: 'applied' }
                   },
                   text: `<span class='excel-export-button'><i class="fa fa-file-excel-o" aria-hidden="true"></i> Export selection to excel</span>`