Update select.js

If selectedItems is an empty array, if(!selectedItems) is still false. It should be if(!selectedItems.length), which evaluates to true if selectedItems is empty.

With the current values, errors occur at line 266, since ctrl.parserResult.source($scope) evaluates to undefined, data does not have the filter method.
Merge pull request #199 from buchelew/patch-1

Update select.js