Add Japanese (#402)

Author: ByteHamster

_config.yml

@@ -21,7 +21,7 @@ plugins:
 permalink: /:categories/:title
 
 # Localization
-languages: [en, fr, nl, it, da, de, es, fa]
+languages: [en, fr, nl, it, da, de, es, fa, ja]
 # don't forget to add new languages also in _data/locales.yml
 defaultLang: en
 default_locale_in_subfolder: false

_data/locales.yml

@@ -17,3 +17,5 @@
   name: Español
 - code: fa
   name: فارسی
+- code: ja
+  name: 日本語