[DEVISE] upgrade to 1.2

add_encryptable_to_users.rb

# [DEVISE] From version 1.2, there is no need to set your encryptor to
# bcrypt since encryptors are only enabled if you include :encryptable
# in your models. To update your app, please:
# 1) Remove config.encryptor from your initializer;
# 2) Add t.encryptable to your old migrations;
# 3) [Optional] Remove password_salt in a new recent migration. Bcrypt
# does not require it anymore.

# $ rails g migration AddEncryptableToUsers

class AddEncryptableToUsers < ActiveRecord::Migration
  def self.up
    change_table :users do |t|
      t.encryptable
    end
  end
  def self.down
    remove_column :users, :encryptable
  end
end

# $ rake db:migrate