monitor_testcase_3: make file listings consistent

Signed-off-by: Libor Pechacek <lpechacek@suse.cz>
monitor_testcase_3: Check test files in /mnt

Check presence and size of all three test files upon completion.

Signed-off-by: Libor Pechacek <lpechacek@suse.cz>
monitor_testcase_functions: Fix array check in stop_md()

stop_md() can be called before start_md().  In that case there is no valid
initial array state we'd like to compare with current state so we skip the
check.  This patch also makes START_LOG variable available to other users.

Signed-off-by: Libor Pechacek <lpechacek@suse.cz>
monitor_testcase_4: Add checks for timeout condition

As well as a half-way check of the storage array.

Signed-off-by: Libor Pechacek <lpechacek@suse.cz>
monitor_testcase_5: Add checks for timeout condition

And add a half-way check of the storage array.

Signed-off-by: Libor Pechacek <lpechacek@suse.cz>
monitor_testcase_2.sh: Checkpointing

Check whether md_monitor manages to re-add the disks.  That is done by sampling
mdadm --detail and comparing it to the initial array state.  The state must
remain unchanged after test.

Signed-off-by: Libor Pechacek <lpechacek@suse.cz>
monitor_testcase_6: Fail the test if the array has not been properly reconstructed in time

Signed-off-by: Libor Pechacek <lpechacek@suse.cz>