TAJO-1221: HA TajoClient should not connect TajoMaster at the first.

I added a method to update TableStats at CatalogStore. For reference, all unit cases for physical operators verify output row numbers and it finished successfully with my patch. So, I didn't implement unit test cases. In addition, HCatalogStore::updateTableStats is dummy method. Because hive don't provide no api to update table row numbers.
Could you explain its purpose?