qa/354 - rework after pmRecord* changes in libpcp

We use to leave the temporary file basename file after creating
a folio and lots of files using the basename as a prefix.  Not leaving
the unused basename file behind broke this QA test.
Add diagnostic to test qa/354 to help understand a regression
Assorted PMDAs - don't need -ldl in the installed Makefile

Was causing failures on FreeBSD ... we don't need dlopen() and friends
here and even if we did, the correct thing would be $(LIB_FOR_DLOPEN)
from builddefs, not an unconditional -ldl.
For now, disable systemd support for debian builds
Makepkgs - FreeBSD help

gnu_tools() was failing because gunzip does not have gnu.org email
in --help output, but a FreeBSD tag.
build/tar/postinstall.tail - permissions rework

Refactor the post-install permissions fixups.
1. add $PCP_RUN_DIR to the list of dirs to be fixed
2. force chmod, even if directory already exists
strchrnul() is not in libc for FreeBSD

Add configure support and alternate (clean) implementation in libpcp.
qa/GNUmakefile - enumeration of tests was wrong

scriptlet for stripping :reserved and :retired tests from group
file was just plain wrong ... broke the FreeBSD build.
qa/pmdas installed makefiles - -ldl fix

Use $(LIB_FOR_DLOPEN) instead of -ldl.
Merge branch 'dev' of git://git.pcp.io/kenj/pcp into dev