Allow users to set preferred locale in settings and provide basic date and time localization support (#1226)

* Add basic date and time localization

* Normalize translations

* Localize transaction dates

* Removed unsupported Rails locales

app/controllers/concerns/localize.rb

@@ -0,0 +1,13 @@
+module Localize
+  extend ActiveSupport::Concern
+
+  included do
+    around_action :switch_locale
+  end
+
+  private
+    def switch_locale(&action)
+      locale = Current.family.try(:locale) || I18n.default_locale
+      I18n.with_locale(locale, &action)
+    end
+end