Add user mailer from spree_auth_devise

app/mailers/spree/user_mailer.rb

@@ -0,0 +1,12 @@
+module Spree
+  class UserMailer < BaseMailer
+    def reset_password_instructions(user)
+      recipient = user.respond_to?(:id) ? user : Spree.user_class.find(user)
+      @edit_password_reset_url = spree.edit_spree_user_password_url(:reset_password_token => recipient.reset_password_token)
+
+      mail(:to => recipient.email, :from => from_address,
+          :subject => Spree::Config[:site_name] + ' ' + 
+            I18n.t(:subject, :scope => [:devise, :mailer, :reset_password_instructions]))
+    end
+  end
+end