User requires a method to limit the max memory of containers managed by paunch.
Without this, containers can bloat as they wish and also makes memory consumption forecasting unpredictable.

Noting that this is already in the TODO in the builder's code:
https://github.com/openstack/paunch/blob/master/paunch/builder/compose1.py
~~~
  # TODO(sbaker): add missing compose v1 properties:
        # cgroup_parent
        # devices
        # dns, dns_search
        # entrypoint
        # expose
        # extra_hosts
        # labels
        # ports
        # stop_signal
        # volume_driver
        # cpu_quota
        # cpuset
        # domainname
        # hostname
        # mac_address
        # mem_limit
        # memswap_limit
        # mem_swappiness
        # read_only
        # shm_size
        # stdin_open
        # working_dir
~~~

Cheers,
Marc Methot