HBase should provide a tool to compare 2 remote tables.

As discussed in the mailing list, when a table is copied to another cluster and need to be validated against the first one, only VerifyReplication can be used. However, this can be very long since data need to be copied again.

We should provide an easier and faster way to compare the tables.

One option is to calculate hashs per ranges. User can define number of buckets, then we split the table into this number of buckets and calculate an hash for each (Like partitioner is already doing). We can also optionally calculate an overall CRC to reduce even more hash collision.