ActionMailer设置发送邮件的地址用户名之类的放在environment里面可以，放在development里面不行。

environment文件里：

ActionMailer::Base.smtp_settings = {
:address => "smtp.gmail.com",
:port => 587,
:authentication => 'plain',
:user_name => 'xxxxx',
:password => 'xxxxx',
:enable_starttls_auto => true
}