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)


mysql-test/include/ps_query.inc:
  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)
mysql-test/r/ps_2myisam.result:
  results updated
mysql-test/r/ps_3innodb.result:
  results updated
mysql-test/r/ps_4heap.result:
  results updated
mysql-test/r/ps_5merge.result:
  results updated
mysql-test/r/ps_6bdb.result:
  results updated
sql/sql_select.cc:
  don't shortcut - it backfires!
  (in particular - when itemptr is Item_param :)