Add some debian packaging.
upstart: Fix starting conditions

postgresql is not controlled by upstart yet, so the original condition is
never triggered.
debian: Add cgroup-bin as dependency

Something has to mount /sys/fs/cgroup/. We could do it manually, but that seems
improper. Depending on cgroup-bin may be overkill, but it seems like any
craziness required to mount /sys/fs/cgroup/ in various circumstances would be
already handled by it, now and in the future.