OSX - more build/install tweaks

Firstly, make sure /Library/StartupItems/pcp/pcp exists - it is used
by various pre/post install scripts but symlink got misplaced in
some re-shuffle.

Secondly, fix typos in uinstall-pcp.in
qa/622 - add notrun guard if host $PCPQA_HYPHEN_HOST is not pingable
qa/828 - improved valgrind suppressions
qa/828 - pdu buffer pool size is not constant

Accommodate different platforms ... what is important that the number
of buffers does not grow without bound.   Increased the iteration count
from 10 to 20.
qa/admin/pcp-daily & qa/admin/pcp-qa-summary

- pcp-daily - add another FreeBSD host to the special case
- pcp-qa-summary - report % failures across all hosts, and add -f
  to sort the failure map by ascending failure %
qa/828 - more valgrind suppression tweaks

paranoidLogRead() may not be inlined, and then appears as a
additonal call frame between __pmGetArchiveEnd() and __pmLogRead().
qa/828 - bad valgrind tap dance

Appears cause is not gcc version, nor valgrind version, but 32-bit
CPU (i586 or i686 so far).
qa/833 & qa/churnctx.c

Similar changes to 822.  PDU buffer pool usage is not quite
deterministic, so relax filtering and be a little more relaxed
in churnctx before reporting an apparent leak.
qa/admin/allow-pmlc-access - QA Helper

For distributed QA to work, we need each QA machine to be able to
run pmlc to connect to the primary pmlogger on each other QA machine.

This script amends the config.default pmlogger configuration file to
allow unlimited pmlc access from hosts on the same IPv4 network.

Works for me in Carnegie ... others may need to extend to suit their
local needs.
qa/828 - more valgrind mumbo jumbo

On some platforms, the call stack ends at memalign <- valloc, rather
than at malloc.  Add alternative suppressions for these ones.
qa/common.filter - tweak _filter_views()

When QA is run from cron, dbus gets in the way even more, so add extra
filtering.
qa/admin/pcp-qa-summary - add header lines every 20 lines of output

Too many failures and I lose track in the failure map.
qa/admin/check-vm - use same logic as allow-pmlc-access for IPv4 addr of local network
qa/common.filter - another dbus error message to dodge
qa/common.filter - oops, fix last sed botch
qa/755 - add short sleep to try and dodge slow start race
qa/README - add note about firewalls and QA needs
qa/755 - better pmcd stop filtering
Teach check-statics new OSX tricks

OSX 10.9 changed the way symbols are used: they now use L___func__. prefix
for __func__ macro expansion, L_str. for strings and they also pre-prepend
the scope names to statics so 'static char *foo' declared in function bar
is called bar.foo - all that is filtered in check-statics.
qmake fix - ugly

qmake appears to be broken in that the generated Makefile contains a
bogus -L/some/lib/dir component _before_ the PCP and related lib
dirs we care about.

If a down-rev libpcp, for example, is installed on /some/lib/dir, we
try to link against the down-rev libpcp instead of the correct one in
the build ... discovered by Jeff Hanson @ SGI.

The fix is to edit the Makefile after qmake generates it and before we
use it in the build.