FreeNAS Code

use HEALTHY instead of ONLINE for volume status

use ONLINE for volume status even for gmirror,gstripe,graid3 (UP,COMPLETE);
move status check from MountPoint to Volume

let middleware also handle nut_ups{log,mon} services

- Make it possible to label a disk without using swap;
- By default, don't allocate swap space on ZIL and cache devices,
these devices tends to be replaced as a whole.

Fix for ntfs volume import

Don't request for 4k hack when adding more disks to pool.

Reported by: jpaetzel

handle unavail = not ONLINE
use disk_name to detach an unavail disk from a pool

Restructure 4K disk handling:

- Only taste disk for 4k when we don't know we are going to do 4k disks.
Also, taste only the first disk rather than all disks;
- Remove _init_zfs_disk which is bitrot and not unused.

- Extract common code for ZFS vdev manipulation into one __prepare_zfs_vdev
and eliminate the duplicated code;
- aclmode=passthrough and aclinherit=passthrough should be set at creation
time rather than after creation;
- reload_disk() only at last.

Split the partitioning into another sequence so no cache invalidation is
needed for every disk but only once after we finished everything.