/var/log/qubes directory have setgid set, so all the files will be owned
by qubes group (that's ok), but there is no enforcement of creating it
group writable, which undermine group ownership (logs created by root
would not be writable by normal user)
QubesOS/qubes-issues#2412
logging.getLogger when given the same name twice, will return the same
object. Do not attach handler there every time, it will really open new
file, leading to multiplicated log entries and depleting file
descriptors.
QubesOS/qubes-issues#1697
