Japanese language files added, and arranged footer parameters together in configuration manager

This pull request contains two commits. The first commit is Japanese translation of language files.
 
The second commit is to improve looks of parameter order in the configuration manager. 
During translation work, I found that `showlink` parameter does not relate to the footer items displayed just under the included part, but located between `showfooter` and `showpermalink` in the configuration manager. It makes me confused to get better understanding on plugin configuration.