New ZFSv28 patchset for 8-STABLE

[Rich]

Hi world,
I've tested with ZFSv28 on RELENG_8 using the patch
http://people.freebsd.org/~mm/patches/zfs/v28/releng-8.2-zfsv28-20110204.patch.xz
.

I can reproducibly panic it using the following sequence of three steps:
# dd if=/dev/zero of=sparse_file bs=1M count=2000000
# zpool create testv28 raidz1 ad20 ad26 `pwd`/sparse_file
# zpool offline testv28 `pwd`/sparse_file

At step 3, I panic every time. I am attempting to get a crash dump, but for
whatever reason, the dump appears to be hanging instead of making any
progress.

- Rich