Add Japanese translation (blogs.json)

- Add Japanese decriptions for links in blogs.json
Add Japanese translation (conferences.json)

 - Add Japanese decriptions for links in conferences.json
Add Japanese translation (podcasts.json)

 - Add Japanese decriptions for links in podcasts.json
Add Japanese translation (weekly.json)

 - Add Japanese decriptions for links in weekly.json
Merge pull request #80 from YasuhiroYoshida/develop2

Add Japanese descriptions of links