[master] Fix many or all 'cannot commit to disk after 5 attempts' problems

[David Cantrell]

The problem I have been able to reliably reproduce is active logical volumes
on the system when the storage code goes to commit changes to the disk.

Added a status() property to LVMLogicalVolumeDevice that calls lvm.lvs() and
reads the lv_attr field looking for an 'a' which indicates the logical volume
is active.  This patch causes the rest of the LVM device status code to fall
in to place and the devices are torn down/deactivated correctly.