FreeNAS Code

Try to cache confxml but not too aggressively.

half-way solution for zfs disk replacement

introduce a Pool object while keeping the legacy API for now

middleware method to parse a given pool name

Don't do down-then-up cycle when starting if IPv6 is already
enabled.

move some classes/method related to zfs for future use in replacement;
a lot of work is still required for a better API for a more pythonic
way of retrieving the state of the pool

Merge in a few revisions from iXsystems' repository:

- Use -f when attaching zpool vdev. In the case the device is not totally
erased, we would not be able to attach them without this change.
- Eliminate unneeded multiple zfs get runs. This is mostly a rewrite of
zfs_get_options by adopting get_zfs_attributes's ideas that only runs
zfs(8) once and get all attributes in a batch.
- Remove the unused [sg]et_zfs_attribute[s].

make sure newfs for single disk doesnt hit the .wait() pipe limit

Oops. Forgot some d's.

Make notifier aware of ix-syslog.