tests: Remove ancient SCCS tags.

Remove ancient SCCS tags from the tree, automated scripting, with two
minor fixup to keep things compiling. All the common forms in the tree
were removed with a perl script.

Sponsored by: Netflix

Remove $FreeBSD$: one-line sh pattern

Remove /^\s*#[#!]?\s*\$FreeBSD\$.*$\n/

ZFS: fix several of the "zpool create" tests

* Remove zpool_create_013_neg. FreeBSD doesn't have an equivalent of
Solaris's metadevices. GEOM would be the equivalent, but since all geoms
are the same from ZFS's perspective, this test would be redundant with
zpool_create_012_neg

* Remove zpool_create_014_neg. FreeBSD does not support swapping to regular
files.

* Remove zpool_create_016_pos. This test is redundant with literally every
other test that creates a disk-backed pool.

* s:/etc/vfstab:/etc/fstab in zpool_create_011_neg

* Delete the VTOC-related portion of zpool_create_008_pos. FreeBSD doesn't
use VTOC.

* Replace dumpadm with dumpon and swap with swapon in multiple tests.

* In zpool_create_015_neg, don't require "zpool create -n" to fail. It's
reasonable for that variant to succeed, because it doesn't actually open
the zvol.

* Greatly simplify zpool_create_012_neg. Make it safer, too, but not
interfering with the system's regular swap devices.

* Expect zpool_create_011_neg to fail (PR 241070)

* Delete some redundant cleanup steps in various tests

* Remove some unneeeded ATF timeout specifications. The default is fine.

PR: 241070
MFC after: 2 weeks
Sponsored by: Axcient

Add the ZFS test suite

It was originally written by Sun as part of the STF (Solaris test framework).
They open sourced it in OpenSolaris, then HighCloud partially ported it to
FreeBSD, and Spectra Logic finished the port. We also added many testcases,
fixed many broken ones, and converted them all to the ATF framework. We've had
help along the way from avg, araujo, smh, and brd.

By default most of the tests are disabled. Set the disks Kyua variable to
enable them.

Submitted by: asomers, will, justing, ken, brd, avg, araujo, smh
Sponsored by: Spectra Logic Corp, HighCloud