- Bug #985: "Between RESET SLAVE and START SLAVE, SHOW SLAVE STATUS is wrong."
Now RESET SLAVE puts correct info in mi->host etc. A new test rpl_reset_slave
for that.
- Bug #986: "CHANGE MASTER & START SLAVE do not reset error columns in SHOW
SLAVE STATUS". Now these reset the errors.


mysql-test/r/rpl_loaddata.result:
  result update.
mysql-test/t/rpl_loaddata.test:
  Test that RESET SLAVE, START SLAVE and CHANGE MASTER all reset 
  Last_slave_error and Last_slave_errno (columns of SHOW SLAVE STATUS).
  We do it in this test because that's one of tests which have 
  an intentional query error on the slave.
sql/slave.cc:
  As we need TWICE the code to copy command-line options (--master-host etc)
  to mi (we already had it in init_master_info, but we also need it in RESET
  SLAVE to fix bug#985), I make a function of this code.
  And a function to reset Last_slave_error and Last_slave_errno (we need
  it in CHANGE MASTER, RESET SLAVE, and at the start of the SQL thread).
sql/slave.h:
  declarations for new functions.
sql/sql_repl.cc:
  copy --master-host etc to mi in RESET SLAVE, so that SHOW SLAVE STATUS
  shows correct information.