15.04 vivid / systemd changes cgroup pathing

[csherwood]

testing out vivid which comes with systemd by default. the cgroup pathing is changed, which slightly breaks this great utility.

hacked together a quick fix, thought you might be interested:

supported_cgroups()

-lscgroup | awk -F: "/$ID/ {print $1}" | paste -sd,
+lscgroup | awk -F: "/$ID/ {print $1}" | uniq | paste -sd,

inside()

-cgexec -g "$(supported_cgroups "$ID"):docker/$ID" --
+cgexec -g "$(supported_cgroups "$ID"):/system.slice/docker-$ID.scope" -- \