Add vendor import for pjdfstest

This vendor import code was obtained from
https://github.com/pjd/pjdfstest/commit/abf03c3a47745d4521b0e4aa141317553ca48f91

Approved by: rpaulo (mentor)
Phabric: D743
Sponsored by: EMC / Isilon Storage Division
Have distrib-dirs, distribution, hier, hierarchy, redistribute, and reinstall
depend on the .MAKE special target

This will allow users to do something like the following to print out the
results of the running the simulated make target with bmake, like some of the
other top-level make targets in Makefile.inc1:

  % make -f Makefile.inc1 -n distribution TARGET=i386 TARGET_ARCH=i386

MFC after: 2 weeks
Sponsored by: EMC / Isilon Storage Division
Clean the generated baseline files by adding them to CLEANFILES.
Improve bsd.progs.mk compatibility with bsd.prog.mk

1. Do not install FILES/SCRIPTS multiple times if PROGS is specified; this is
   already handled via bsd.prog.mk when it's called recursively (PR: 191055,
   191955).
2. Some variables, like BINDIR and PROGNAME, default to a value if unset
   whereas others get appended to, like CFLAGS. Add support for the former case
   (PR: 191056)
3. Make "checkdpadd" and "clean" available targets for recursive execution.

Reviewed by: marcel, sjg
Phabric: D822
PR: 191055, 191056, 191955
MFC after: 1 week
Sponsored by: EMC / Isilon Storage Division
Fix a typo in the upgrade directions

MFC after: 2 weeks
Sponsored by: EMC / Isilon Storage Division
Import pjdfstest from ^/vendor/pjdfstest/abf03c3a47745d4521b0e4aa141317553ca48f91

- Remove tools/regression/pjdfstest
- Add upgrade directions for contrib/pjdfstest
- Add a note to UPDATING for the move (the reachover Makefiles are coming
  soon)

Functional differences:
- ftruncate testcases are added from upstream (github)

Non-functional differences:
- The copyright for the project has been updated to 2012
- pjd's contact information has been updated

Discussed with: -testing, jmmv, pjd
MFC after: 2 weeks
Sponsored by: EMC / Isilon Storage Division
Remake Linux' SOUND_MIXER_INFO IOCTL as a wrapper around new FreeBSD's one.

Submitted by:	Dmitry Luhtionov <dmitryluhtionov@gmail.com>
MFC after:	3 days
Update code to use new network counter API.
Fix some minor compile warnings while at it.

Sponsored by:	Mellanox Technologies
Suggested by:	glebius@
MFC after:	1 week
Merge remote-tracking branch 'freebsd/master' into hardened/current/segvguard