doc: Update Japanese lxc-ls(1) for -f and -F option

Update for commit c5afb6e455d9ec00af9f3399836152eaf9d0a4f5

Signed-off-by: KATOH Yasufumi <karma@jazz.email.ne.jp>
Acked-by: Stéphane Graber <stgraber@ubuntu.com>
lxc-usernsexec: add a manpage

and fix the help output in the program

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