(WL#794). This can be of interest in some recovery-from-backup scenarios, and also when you have
two databases in one mysqld, having a certain similarity and you want one db to be updated when the other is
(some sort of trigger).
Plus small fix for BUG#3568 "MySQL server crashes when built --with-debug and CHANGE MASTER +MASTER_POS_WAIT"


sql/mysqld.cc:
  new option --replicate-same-server-id
sql/slave.cc:
  new option replicate_same_server_id, to force a slave to execute its own queries.
  Small fix for BUG#3568 "MySQL server crashes when built --with-debug and CHANGE MASTER +MASTER_POS_WAIT"
sql/slave.h:
  new option --replicate-same-server-id