Fix/import file

Closes #268 (closed)

smash/web/api_views/worker.py

@@ -35,7 +35,7 @@ def workers_for_daily_planning(request):
         role = unicode(worker.roles.filter(study_id=GLOBAL_STUDY_ID)[0].role)
         worker_dict_for_json = {
             'id': worker.id,
-            'flags' : [language.image.url for language in worker.languages.all()],
+            'flags' : [language.image.url for language in worker.languages.all() if language.image],
             'availability': worker.availability_percentage(start_date=start_date),
             'title': u"{} ({})".format(unicode(worker), role[:1].upper()),
             'role': role