lxc-ls: Fix memory reporting

This resolves the memory math when memsw is enabled and fixes reporting
of nested containers memory when using cgmanager.

Signed-off-by: Stéphane Graber <stgraber@ubuntu.com>
Acked-by: Serge E. Hallyn <serge.hallyn@ubuntu.com>
lxc-ls: Optimize things a bit

Don't bother access information that the user didn't request.

Signed-off-by: Stéphane Graber <stgraber@ubuntu.com>
Acked-by: Serge E. Hallyn <serge.hallyn@ubuntu.com>
userns: Update bind-mounted devices

This updates all configs to include the exact same set of 7 bind-mounted
devices:
 - console
 - full
 - null
 - random
 - tty
 - urandom
 - zero

Signed-off-by: Stéphane Graber <stgraber@ubuntu.com>
Acked-by: Serge E. Hallyn <serge.hallyn@ubuntu.com>