Putting kerberos/ldap logs somewhere useful

I got frustrated just now because this:

https://buildfarm.postgresql.org/cgi-bin/show_log.pl?nm=crake&dt=2019-08-05%2021%3A18%3A23

is essentially undebuggable, thanks to the buildfarm's failure to
capture any error output from slapd. That's not the buildfarm
script's fault: it's willing to capture everything placed in the
agreed-on log directory. But the TAP test script randomly places
the daemon's log file somewhere else, one level up. The kerberos
test script has the same problem.

Hence, I propose the attached. This just moves the actual log
files ... we could possibly move the daemons' .conf files as well,
but I think they're probably not variable enough to be interesting.

regards, tom lane