Add Indonesian (Bahasa Indonesia / id) translation (#2200)

* add Indonesian (Bahasa Indonesia) translation

add id.jsx
add translations on email views
add devise.id.yml
add doorkeeper.id.yml
add id.yml
add simple_form.id.yml

update id locale on mastodon.jsx, index.jsx, settings_helper.rb, and
application.rb

* add Indonesian (Bahasa Indonesia) translation

add id.jsx
add translations on email views
add devise.id.yml
add doorkeeper.id.yml
add id.yml
add simple_form.id.yml

update id locale on mastodon.jsx, index.jsx, settings_helper.rb, and
application.rb

* fix InvalidLocaleData on a string

* fix InvalidLocaleData on a string

* Fix language keys in Indonesian ruby locale (id)

Use "id" instead of "en" as object keys.

* Removed obsoleted translation (id)

app/helpers/settings_helper.rb

@@ -25,6 +25,7 @@ module SettingsHelper
     'zh-HK': '繁體中文（香港）',
     'zh-TW': '繁體中文（臺灣）',
     bg: 'Български',
+    id: 'Bahasa Indonesia',
   }.freeze
 
   def human_locale(locale)