FreeNAS Code

add field to limit replicationm speed using throttle pipe;
add userepl field in Replication to migration as well, seems forgotten

Checkpoint. Don't use this.

Add an option to use the '-R' option of zfs send.

While I'm there fix the issue that if the remote side deleted all
snapshots, the replication doesn't start over.

Rate limit messages.

Fixes #383.

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.

Fat fingerness fixed.

PITA. ZFS legwork is done I believe.

Just saving work. Nothing works yet ;-)

Fat fingered some lines, fixed. Added cron.

Initial import of this, currently doesn't actually import anything, just
spits out SQL. Various methods need to be fully implemented and data
needs to be sanitized, so, lots of work still needed.