fix arch typo

Signed-off-by: Hiroshi Miura <miurahr@linux.com>
add plugin version

- retrieve version number from rubygems.org
  just call `rake plugin_version`

Signed-off-by: Hiroshi Miura <miurahr@linux.com>
split usecase from config listing

Signed-off-by: Hiroshi Miura <miurahr@linux.com>
change tab to box configs

Signed-off-by: Hiroshi Miura <miurahr@linux.com>