(pre-push cleanups removing debugging code)

- fix problem with too long identifier name

- fix crash of an event that alters itself
- make "alter event xyz;" invalid because at least 1 clause is needed.

- enable/disable -> enabled/disabled
- fixed error message

- improve the stability of the executor
- make create event if not exists work as before

- fix one bug found by PeterG, namely bug #51

#there is a major problem currently after removing the specialised DYNAMIC_ARRAY as 
  storage for the events. I have to reintroduce similar storage, this time probably some
  linked list or maybe some API on top of DYNAMIC_ARRAY.

- varchar -> char
- transient_expression -> interval_value
- interval_type -> interval_field

- handle crashes where the table definition has been changed
  (different number of fields)

fix bug with DROP EVENT non_existant; giving back OK + warning

make compile-pentium-debug-max work

- fix EVENT_ACL problem that GRANT ALL on some_db.* to someone@somewhere did not get to mysql.db
- fix crash when the following is executed :
  CREATE EVENT P() CREATE EVENT E ON SCHEDULER 1 SECOND DO ROLLBACK;
  (creation works as well as calling P() which creates the event).

into lmy004.:/work/mysql-5.1-tt-copy-works

- fixed silly bug, the main thread restarted but did not execute events,
  Quite currious why many calls to pthread_mutex_init() do not lead to abort()

(cleanups, leaks fixed)

cleanup before throwin away DYNAMIC_ARRAY for event storage,
once reallocated I get dangling pointers so that's not good.
solution will be found however ;)

QUEUE implementation working now. this should be ready more or less
for testing once the debug output is being cleaned and some things
around DYNAMIC_ARRAY are cleaned
- fix handling in case of errors that lead to crashes, now no more crashes
  in case of table corruption and such.

- handle better non-latin1 identifiers

- fix a bug introduced with last commit ALTER EVENT a RENAME TO b; failed
- misc

(strip m_ as prefix from member variables' names)

make more independent of SP

updated sources

- split into several files
- forbid parallel execution (before analyse is done how to make it possible)
  because the same sp_head instance cannot be executed in parallel
- added GPL headers
- changed EVENT_ACL to be per DB variable
- fixed minor problems

into  mysql.com:/users/emurphy/src/mysql-5.1-new

into  mysql.com:/users/emurphy/src/mysql-5.1-new

Now when rolling back a transaction on a blackhole table,
the transaction will not be written to the binlog.

into  mysql.com:/home/jimw/my/mysql-5.1-clean

into  selena.:H:/MYSQL/bkt/mysql-5.1

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

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

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

into  selena.:H:/MYSQL/src/#14902-mysql-5.0

into  mysql.com:/home/timka/mysql/src/5.1-dbg