FIX: imex module cancel bug

Author: MCStreetguy

lib/imex.js

@@ -61,12 +61,11 @@ export default class IMEX {
       properties: ['openFile'],
       filters: filters
     },function(filenames) {
-      var filename = filenames[0];
-      if(Util.isset(filename,'string')) {
-        var temp = path.extname(filename).replace('.','').toLowerCase();
+      if(Util.isset(filenames,'object') && Util.isset(filenames[0],'string')) {
+        var temp = path.extname(filenames[0]).replace('.','').toLowerCase();
         switch(temp) {
           case 'csv':
-            _this._impcsv(filename);
+            _this._impcsv(filenames[0]);
             return true;
             break;
           default: