MFC zfs manpage update

MFC zfs manpage update
(r227646, r227648, r227649, r227752, r228019, r228045, r228054, r228055)

MFC r227646 (partial):
Update and desolarization of zfs(8) and zpool(8) manual pages:
- synchronized to match new vendor code (Illumos rev. 13513) [1]
- removed references to sun commands (replaced with FreeBSD commands)
- removed ATTRIBUTES sections
- updated SEE ALSO sections
- properly updated copyright information (required by CDDL)

zfs(8) only:
- replaced "Zones" section with new "Jails" section
- removed misleading "ZFS Volumes as Swap or Dump Devices" section
- updated shareiscsi and sharesmb option information (not supported on FreeBSD)
- replace zoned property with jailed property

zpool(8) only:
- updated device names in examples

MFC r227648:
Fix reference to fsync(2).
Add more references to SEE ALSO section.

MFC r227649:
More zfs(8) manpage fixes:
- remove shareiscsi property
- mark casesensitivity property as unsupported
- remove reference to Solaris Administration Guide

MFC r227752 (partial):
Update and desolarization of zdb(8) and zstreamdump(1) manual pages:
- synchronized to match new vendor code [1]
- removed ATTRIBUTES sections
- updated SEE ALSO sections
- properly updated copyright information (required by CDDL)

MFC r228019:
Update ZFS manual pages to a mdoc(7) reimplementation.

The zfs(8) and zpool(8) manual pages now match the state of the ZFS module
and have been customized for FreeBSD.

The new texts of the "Deduplication" subsection in zfs(8), the zpool "split"
command, the zfs "dedup" property and several other missing parts have been
added from illumos or OpenSolaris snv_134 (CDDL-licensed).

The mdoc(7) reimplementation of whole manual pages, the descriptions of the
zpool "readonly" property, "zfs diff" command and descriptions of several
other missing command flags and/or options were authored by myself.

MFC r228045:
Add missing -n flag to "zpool import" description.

MFC r228054:
Add missing warning to zfs(8) for using "zfs destroy" with -r and -R flags.

MFC r228055:
Use singular form for zfs destroy snapshot in zfs(8).

Obtained from:	Illumos (as of rev. 13513:f84d4672fdbd) [1]

git-svn-id: svn://svn.freebsd.org/base/stable/8@229577 ccf9f872-aa2e-dd11-9fc8-001c23d0bc1f