Remove stale log files and speed up apache log sync * Major speedup: The apache log directory was pointlessly being copied for each user on each sync so that it could be chowned and transferred. But there is no need: afs ignores the owner/group and unix permissions and root can read the keytabs. Eliminating the redundant copy sped the script by from ~9 minutes to ~2 minutes. * Limit scope of each transfer to the per-host apache log directory. This could result in less stat()ing, but more importantly allows us to... * Pass --delete to rsync to clean up stale log files. It turns out that for a very long time we've just been leaving the uncompressed logrotated apache logs behind, and never removing old log files. Fix that.