sync using replicate-wild-ignore-table
Problem: changes in character set variables
before an action on an replication-ignored table
makes slave to forget new variable values.
Fix: initialize one_shot variables only when
4.1 -> 5.x replication is running.


mysql-test/r/rpl_ignore_table.result:
  Adding test case
mysql-test/t/rpl_ignore_table-slave.opt:
  Don't replicate tables with names starting with "tmptbl"
mysql-test/t/rpl_ignore_table.test:
  Adding test case
sql/sql_parse.cc:
  Reset one_shot variables only if we do 4.1->5.x replication.
  In other cases we cannot do that: resetting thd->variables out of sync with
  st_relay_log_info::cached_charset, which makes
  st_relay_log_info::cached_charset_compare() not to notice
  character set related variables changes afterwards.