support added to maria.


mysql-test/r/maria.result:
  New variables added.
storage/maria/ha_maria.cc:
  Variable for transactional log purge method added.
  Variable for transactional log size added.
  SHOW for engine logs added.
  Log flush purge logs in case of "ondemand" type of
    log processing.
storage/maria/ma_checkpoint.c:
  log purge call enabled.
storage/maria/ma_loghandler.c:
  Support for different methods of log purge added.
  Functions for getting information about logs state added.
  Functions for getting/setting log size.
storage/maria/ma_loghandler.h:
  Fixed defines.
  Functions for for transactional log mannegment added.
storage/maria/ma_recovery.c:
  Dependence on TRANSLOG_FILE_SIZE removed.
mysql-test/r/maria-purge.result:
  New BitKeeper file ``mysql-test/r/maria-purge.result''
mysql-test/t/maria-purge.test:
  New BitKeeper file ``mysql-test/t/maria-purge.test''