pndnotifyd logging was already available (just drop the -d on command line, and redir...

pndnotifyd logging was already available (just drop the -d on command line, and redirect to file; log level was in conf file..)
 -- but now you can just add -l to command line to cause it to go go debuglevel and spit out to /tmp/pndnotifyd.log
 -- can actualyl do -l#, where # is log level, default is 0 (all)

pnd_logger now has set_buried_logging() which lets you turn on logging in libpnd API that doesn't normally log, such as
the discovery code; this way we can log some deep-shit, if we really want to