- 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.


sql/event.cc:
  close the table
sql/event.h:
  change definition
sql/event_executor.cc:
  don't start the thread in advance
sql/event_timed.cc:
  - don't call evex_drop_event
  - quote the name during compilation to make create event `the rain in spain goes into the drain` not fail.