Faker::Address.postcode (locale=ja) should contains hyphen

[gongo]

Issue#

• add Japanese actual zipcodes in locals/ja.yml #2297
• Split JA translation file into one file per class #2315

Description:

1️⃣ Bug 1

Since #2297, Japanese postcode no longer contains hyphens.

$ bundle exec irb
irb(main):001:0> require 'faker'
=> true
irb(main):002:0> Faker::Config.locale = :ja
=> :ja
irb(main):003:0> Faker::Address.postcode
=> "8710704" # Expected "871-0704"

2️⃣ Bug 2

Fix indentation for ja/color.yml.

$ bundle exec irb
irb(main):001:0> require 'faker'
=> true
irb(main):002:0> I18n.t('faker.color.name', locale: :ja)
=> "translation missing: ja.faker.color.name"
irb(main):003:0> I18n.t('faker.name', locale: :ja)
=> ["赤", "緑", "青", "黄", "紫", "ミントグリーン", "ティール", "白", "黒", "オレンジ", "ピンク", "灰色", "栗 色", "バイオレット", "ターコイズブルー", "タン", "空色", "サーモン", "プラム", "オーキッド", "オリーブ", "マゼンタ", "ライム", "アイボリー", "藍色", "金", "フクシア", "シアン", "紺碧", "ラベンダー", "銀"]

Due to this effect, the definition of ja/name.yml was overwritten.

irb(main):007:0> Faker::Config.locale = :ja
=> :ja
irb(main):008:0> Faker::Name.first_name
=> "Brandon" # raise `I18n::MissingTranslationData` 'ja.faker.name.first_name`

[vbrazo]

LGTM