SUPER is not required to change binlog format for session
A user without SUPER privileges can change the value of the
session variable BINLOG_FORMAT, causing problems for a DBA.
This changeset requires a user to have SUPER privileges to
change the value of the session variable BINLOG_FORMAT, and
not only the global variable BINLOG_FORMAT.
mysql-test/suite/binlog/t/binlog_grant.test:
Adding test to test grants needed for SQL_LOG_BIN and BINLOG_FORMAT.
sql/set_var.cc:
Adding code to check that user has SUPER permission
needed to change the value of BINLOG_FORMAT.
sql/set_var.h:
Adding function sys_var_thd_binlog_format::check()
