FreeNAS Code

add method to get device name of a vdev from devname

fix serial_from_device regex and device_to_indentifier output for serial

label new geom with geom_name not u_name

remove unused regex

change g{mirror,raid3,stripe} detection and status to use xml

fix auto import for ufs (including the ones not created by fn8)

remove code duplication for smartctl (disk serial)

be more careful with subprocess.wait and remove it from places where deadlock is remotely possible

Refactor automatic replication/snapshotting process:

- Decouple replication from snapshotting. This makes it possible for the
snapshotter to take snapshots while replication is in progress.
- Implement a set of locking mechanism to prevent parallel issue.
- Protect "held" snapshots from being destroyed, this includes the last
snapshot we have replicated for an incremental transfer, the in-progress
snapshots.
- Try harder to recover from failed transfers.

Instead of setting a hard-coded mountpoint, use altroot to enforce the
desired hierarchy.

Add a simple handler to ix-zfs so it handles migration on boot.

While I'm there also slightly restruct the code to reduce duplication.