illumos gate

As per https://github.com/illumos/ipd/blob/master/ipd/0010/README.md

Testing done (mostly on illumos-joyent with some re-verifying):

pgrep -d, postgres
pgrep -ld, postgres
pgrep -fl postgres, check output is modified args where necessary
pgrep -x with/without -f
pgrep -f is stripping trailing blanks
pgrep output of non-control chars, junk etc. (argv-junk.c)
pgrep with very long argv
pgrep with SHORT_PSARGS set
pkill as above

process with > 4096 argv0 string as well as total longer, shorter argv⁰, verify output
ps output of non-control chargs (argv-junk.c)
ps -ef output with changed argv
ps -e output
ps with SHORT_PSARGS
ps aux, auxw, auxww behave as expected with large and small terminals

ps -o pid,comm,fname,args

pargs -e, not -e sanity check

test of cmdline file, ps, top, etc. in an lx zone

cat /proc/*/cmdline - including zsched, sched, etc.

check zone filtering of /proc/*/cmdline works as expected