made smtp sender address configurable

config/app_config.yml.example

@@ -17,6 +17,7 @@ default:
   smtp_port: '587'
   smtp_domain: 'mail.example.com'
   smtp_authentication: 'plain'
+  smtp_sender_address: 'no-reply@example.com'
   smtp_username: 'no-reply@example.com'
   smtp_password: 'secret'
 

config/initializers/devise.rb

@@ -6,7 +6,7 @@
 # four configuration values can also be set straight in your models.
 Devise.setup do |config|
   # Configure the e-mail address which will be shown in DeviseMailer.
-  config.mailer_sender = "please-change-me@config-initializers-devise.com"
+  config.mailer_sender = APP_CONFIG[:smtp_sender_address]
 
   # ==> ORM configuration
   # Load and configure the ORM. Supports :active_record (default), :mongoid