When configuring the dir for the pidfiles in our init scripts don't
assume the path is /var/run/$NAME. The defaults are now /var/run/zuul
now and could be set to other values as well. Instead of assuming
/var/run/$NAME we instead take the dirname of $PIDFILE and configure
whatever that dir is instead.
Change-Id: Idfd5d19e5171278b9bb7005edb4ae927a01f3615