Improve ContactMailer

- Add detailed registrar info
- Refactor contact domain list
- Fix english translation

#480

app/presenters/registrant_presenter.rb

@@ -8,6 +8,7 @@ class RegistrantPresenter
            :reg_no,
            :street, :city, :state, :zip, :country,
            :ident_country,
+           :used?,
            to: :registrant
 
   def initialize(registrant:, view:)
@@ -23,6 +24,17 @@ class RegistrantPresenter
     registrant.ident_country.translation(locale)
   end
 
+  def domain_names_with_roles(locale: I18n.locale, line_break: "\n")
+    lines = []
+
+    registrant.domain_names_with_roles.each do |domain_name, roles|
+      lines << "#{domain_name} (#{roles.map { |role| role.to_s.classify.constantize.model_name.human(locale: locale) }
+                                      .join(', ')})"
+    end
+
+    lines.join(line_break)
+  end
+
   private
 
   attr_reader :registrant