- Added a hash to keep track of database-table pairs.
- Specified database-table tables do not get dumped


client/client_priv.h:
  WL#2319 V2: Exclude tables from dump
client/mysqldump.c:
  WL#2319 V2: Exclude tables from dump
mysql-test/r/mysqldump.result:
  WL#2319 V2: Exclude tables from dump
mysql-test/t/mysqldump.test:
  WL#2319 V2: Exclude tables from dump