我添加了Devise gem,然后按照说明运行rails generate devise:install,结果如下:
/usr/local/rvm/gems/ruby-1.9.3-p194/gems/devise-3.2.4/lib/devise/rails/routes.rb:487:in `raise_no_secret_key': Devise.secret_key was not set. Please add the following to your Devise initializer: (RuntimeError)
config.secret_key = 'abc123'
Please ensure you restarted your application after installing Devise or setting the key.
如何"重启"我的申请？我如何以及在何处设置密钥？