Add apparmor profile for systemd-based containers

Add new apparmor profile, lxc-container-default-with-systemd,
which can be used to start systemd-based containers. Tested for
Fedora 20 and Opensuse 13.1 containers.

This was discussed on lxc-users list:
https://www.mail-archive.com/lxc-users@lists.linuxcontainers.org/msg00995.html
https://www.mail-archive.com/lxc-users@lists.linuxcontainers.org/msg01101.html

Fedora only needs cgroup/systemd mount, while opensuse also needs the bind mount capability.

Signed-off-by: Fajar A. Nugraha <github@fajar.net>