message: Fix for exception message concat
diff: @@ -241,7 +241,7 @@ bool compare_result(string csv, ChunkCollection &collection, vector<SQLType> sql
  parsed_result.Reset();
  reader.ParseCSV(parsed_result);
  } catch(Exception &ex) {
  - error_message = "Could not parse CSV: " + ex.what();
  + error_message = "Could not parse CSV: " + string(ex.what());
  return false;
  }
  if (parsed_result.size() == 0) {
  