Wrap records array in a dictionary

scripts/import-nethack-logfile.py

@@ -114,7 +114,10 @@ def main(argv):
                 'reason_for_death': reason.strip(),
             })
 
-    json.dump(records, sys.stdout, indent=2)
+    output_object = {
+        'records': records,
+    }
+    json.dump(output_object, sys.stdout, indent=2)
     print('\n')
 
 if __name__ == '__main__':