and some SP-related cleanups.

- We don't have separate stage for calculation of list of tables
  to be prelocked and doing implicit LOCK/UNLOCK any more.
  Instead we calculate this list at open_tables() and do implicit
  LOCK in lock_tables() (and UNLOCK in close_thread_tables()).
  Also now we support cases when same table (with same alias) is
  used several times in the same query in SP.

- Cleaned up execution of SP. Moved all common code which handles
  LEX and does preparations before statement execution or complex
  expression evaluation to auxilary sp_lex_keeper class. Now 
  all statements in SP (and corresponding instructions) that
  evaluate expression which can contain subquery have their
  own LEX.

into mysql.com:/home/bk/b7853-mysql-5.0

into mysql.com:/home/kostja/work/mysql-5.0-root

into mysql.com:/home/kostja/work/mysql-5.0-root

reset mysql->net.last_error": the solution is to clear
MYSQL->net error before performing COM_CLOSE: if the call
succeeds, the connection is usable for other statements.
More comprehensive fix is to clear MYSQL->net for all
recoverable errors at the time they happen, it will be
implemented in 5.0 as it introduces incompatibility in behavior.

into neptunus.homeip.net:/home/msvensson/mysql/mysql-5.0

After merge fixes
Don't give duplicate warnings for some ::store() functions

into mysql.com:/home/my/mysql-5.0

into mysql.com:/home/jimw/my/mysql-4.1-clean

into mysql.com:/home/my/mysql-5.0

This removes a (small) memory leak.

into sanja.is.com.ua:/home/bell/mysql/bk/work-4.1

zlib)

into mysql.com:/home/my/mysql-4.1

into mysql.com:/space/my/mysql-4.1-merge

into mysql.com:/space/my/mysql-5.0

- updated mysql-copyright-2 to properly convert this new header from GPL to commercial for the
  commercial distribution

into neptunus.homeip.net:/home/msvensson/mysql/mysql-5.0

into mysql.com:/home/wax/mysql/mysql-5.0

  merged
  auto-union

into mysql.com:/home/wax/mysql/mysql-5.0test

into mysql.com:/home/jonas/src/mysql-4.1

Fix bug in bug fix in FastScheduler
  remove possibility of endless loop
  resulting in APZJobBuffer overflow due to statistics reporting

into serg.mylan:/usr/home/serg/Abk/mysql-5.0