Added Japanese (日本語) (ja) translation. Props Tai.

git-svn-id: https://plugins.svn.wordpress.org/automatic-updater/trunk@685482 b8457f37-d9ea-0310-8a92-e5e31aec5664
Readme typo

git-svn-id: https://plugins.svn.wordpress.org/automatic-updater/trunk@685483 b8457f37-d9ea-0310-8a92-e5e31aec5664
Version: 0.8.4

git-svn-id: https://plugins.svn.wordpress.org/automatic-updater/trunk@685484 b8457f37-d9ea-0310-8a92-e5e31aec5664