sshd: Don't bind-mount /sbin/init read-write

lxc-sshd was mounting itself (the template script) as /sbin/init in the
container using a writable bind-mount.

This shouldn't be needed and could lead to quite a few problems should
one of those containers overwrite /sbin/init for some reason.

Instead simply move to a read-only bind-mount which should prevent any
accidental dammage.

Signed-off-by: Stéphane Graber <stgraber@ubuntu.com>
autostart: Define lxc.start.* and lxc.group

First patch in the set of changes required for container autostart.

This commit adds the new configuration keys and parsers that will then
be used by lxc-start and lxc-stop.

Signed-off-by: Stéphane Graber <stgraber@ubuntu.com>
lxc-ls: Add lxc.start.auto and lxc.group support

Signed-off-by: Stéphane Graber <stgraber@ubuntu.com>
lxc-ls: Add workaround for nested containers

When accessing nested containers, hardcode the path to their config.

Signed-off-by: Stéphane Graber <stgraber@ubuntu.com>
Add lxc-autostart

Signed-off-by: Stéphane Graber <stgraber@ubuntu.com>