zpool-create.sh: allow features to be disabled

The zimport.sh script makes use of the zpool-create.sh script
to construct test pools for importing with older versions of
ZoL.  It is desirable to have a way to disable all the features
so new pools can be imported with older code.

The simplest and most flexible way to achieve this was to merge
the VERBOSE_FLAG and FORCE_FLAG in to a single ZPOOL_FLAGS
variable.  The contents of this variable will be used in the
'zpool create' allowing us to easily pass arbitrary flags.

Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Prakash Surya <surya1@llnl.gov>
Closes #2524
Initial attempt to document events and payloads.

In no way complete - most have been trial and error and some
deducing what they could mean. It needs more information from
someone that knows the code better. But this is a start and
it lays the basic structure for adding this additional detail.

Signed-off-by: Turbo Fredriksson <turbo@bayour.com>
Signed-off-by: Prakash Surya <surya1@llnl.gov>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #2357
Support '-H' (scripted mode) to 'zpool get'

This functionality is already available in 'zfs get'.  Providing
it for 'zpool get' is useful and good for consistency.

Signed-off-by: Turbo Fredriksson <turbo@bayour.com>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes: #2522
Remove patches directory

Support for ZFS has now been merged in to both blkid and grub.
Therefore, there is no longer a need to carry these stale
patches in the ZFS source tree.

Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Illumos 4171, 4172

4171 clean up spa_feature_*() interfaces
4172 implement extensible_dataset feature for use by other zpool features

Reviewed by: Max Grossman <max.grossman@delphix.com>
Reviewed by: Christopher Siden <christopher.siden@delphix.com>
Reviewed by: George Wilson <george.wilson@delphix.com>
Reviewed by: Jerry Jelinek <jerry.jelinek@joyent.com>
Approved by: Garrett D'Amore <garrett@damore.org>a

References:
  https://www.illumos.org/issues/4171
  https://www.illumos.org/issues/4172
  https://github.com/illumos/illumos-gate/commit/2acef22

Ported-by: Tim Chase <tim@chase2k.com>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #2528