CORE: Fixed jdbc data source type for Searcher

- Use NamedParameterJdbcTemplate instead of JdbcTemplate since it can't
  handle named parameters used in Searcher.
- Commented out stdout in Searcher tests.

  Note: Previous SimpleJdbcTemplate (deprecated) combines JdbcTemple and
  NamedParameterJdbcTemplate, so it was possible to pass both types of params
  to the same jdbc template. Now we must choose and pass proper params.