new tests to ensure that prepared statement *really* work
(and that MySQL not picks up some number from arbitrary location
that happens to match the parameter's value)
Note: The following tests fails
- fulltext (Sergei has promised to fix)
- rpl_charset (Guilhem should fix)
- rpl_timezone (Dimitray has promised to fix)
Sanja needs to check out the calling of close_thread_tables() in sp_head.cc
