doc: Update kernel and cgroup info in Japanese lxc(7)

Update for commit 0dcbd62

Signed-off-by: KATOH Yasufumi <karma@jazz.email.ne.jp>
Acked-by: Stéphane Graber <stgraber@ubuntu.com>
lxc-opensuse: template now understands release arguments

Signed-off-by: Johannes Kastl <git@ojkastl.de>
Acked-by: Stéphane Graber <stgraber@ubuntu.com>
lxc-opensuse: Added explanation on how to use the template

Signed-off-by: Johannes Kastl <git@ojkastl.de>
Acked-by: Stéphane Graber <stgraber@ubuntu.com>
lxc-opensuse: Check if given argument is a valid release

Signed-off-by: Johannes Kastl <git@ojkastl.de>
Acked-by: Serge E. Hallyn <serge.hallyn@ubuntu.com>