More DBUG_ASSERT() to discover errors earlier
More checking of BLOCK structures in Aria.
Fixed crashing bug in Aria when doing UPDATE of several records in same block when doing table scan.

storage/federatedx/ha_federatedx.cc:
  Added missing delete_dynamic(); This fixes the valgrind warnings about lost memory discovered by buildbot.
storage/maria/ma_blockrec.c:
  Added debugging helper function _ma_print_block_info() to print block structure.
  Changed arguments to _ma_print_directory() so it can be called by _ma_print_block_info()
  check_directory() now also checks that empty_space on block is calculated correctly.
  Added some local variables to get more information about what happend when things crash.
  Fixed crashing bug when doing UPDATE of several records in same block when doing table scan.
storage/maria/ma_key_recover.c:
  Simple optimization (don't call bmove_upp() if not needed); This could happen during page split.
storage/maria/ma_recovery.c:
  Fixed compiler warning
storage/maria/ma_test2.c:
  Run test without syncing to disk. (Not needed for this test)
storage/maria/ma_write.c:
  More comments.
  Added DBUG_ASSERT() to find wrong log entires, like the one reported at LP#616344, during log file creation.
storage/maria/unittest/ma_test_recovery.pl:
  Added extra -s to maria_chk to get it more silent.
  This fixes that ma_test_all.sh works again.