Convert remaining {g,s}etenv->kern_{g,s}etenv
left over from r273174.

Reported by:    bz
Fix UEFI manpage whitespace and minor issues

Submitted by:	wblock
MFC after:	4 days
Differential Revision: https://reviews.freebsd.org/D959
Use pmc_destroy_pmc_descriptor() to actually free the pmc, which is
consistent with pmc_destroy_owner_descriptor(). Also be sure to destroy
PMCs if a process exits or execs without explicitly releasing them.

Reviewed by:	bz, gnn
MFC after:	2 weeks
Sponsored by:	EMC / Isilon Storage Division
Differential Revision: https://reviews.freebsd.org/D958
* Fix table sets handling.
* Simplify formatting.

Suggested by:	luigi
Fix to col when printing half-line feeds w/ -f option...

Message-Id on openbsd-tech: 20141017195810.GJ132@iris.usta.de
Submitted by:	Ingo Schwarze
Obtained from:	OpenBSD
MFC after:	3 days
sh: Add some tests for backslash-newline continuation.