Hive should support clean-up of previously bootstrapped tables when retry from different dump.

If external tables are enabled for replication on an existing repl policy, then bootstrapping of external tables are combined with incremental dump.
If incremental bootstrap load fails with non-retryable error for which user will have to manually drop all the external tables before trying with another bootstrap dump. For full bootstrap, to retry with different dump, we suggested user to drop the DB but in this case they need to manually drop all the external tables which is not so user friendly. So, need to handle it in Hive side as follows.

REPL LOAD takes additional config (passed by user in WITH clause) that says, drop all the tables which are bootstrapped from previous dump.
hive.repl.clean.tables.from.bootstrap=<previous_bootstrap_dump_dir>

Hive will use this config only if the current dump is combined bootstrap in incremental dump.
Caution to be taken by user that this config should not be passed if previous REPL LOAD (with bootstrap) was successful or any successful incremental dump+load happened after "previous_bootstrap_dump_dir".