不知道为什么我的应用程序不断崩溃。谁能诊断我的问题？这是我的日志：
2012-08-14T20:45:26+00:00 heroku[web.1]: State changed from crashed to starting
2012-08-14T20:45:29+00:00 heroku[web.1]: Starting process with command `bundle exec rails server -p 13851`
2012-08-14T20:45:34+00:00 app[web.1]: DEPRECATION WARNING: You have Rails 2.3-style plugins in vendor/plugins! Support for these plugins will be removed in Rails 4.0. Move them out and bundle them in your Gemfile, or fold them in to your app as lib/myplugin/* and config/initializers/myplugin.rb. See the release notes for more on this: http://weblog.rubyonrails.org/2012/1/4/rails-3-2-0-rc2-has-been-released. (called from <top (required)> at /app/config/environment.rb:5)
2012-08-14T20:45:34+00:00 app[web.1]: DEPRECATION WARNING: You have Rails 2.3-style plugins in vendor/plugins! Support for these plugins will be removed in Rails 4.0. Move them out and bundle them in your Gemfile, or fold them in to your app as lib/myplugin/* and config/initializers/myplugin.rb. See the release notes for more on this: http://weblog.rubyonrails.org/2012/1/4/rails-3-2-0-rc2-has-been-released. (called from <top (required)> at /app/config/environment.rb:5)
2012-08-14T20:45:35+00:00 app[web.1]: => Booting WEBrick
2012-08-14T20:45:35+00:00 app[web.1]: => Ctrl-C to shutdown server
2012-08-14T20:45:35+00:00 app[web.1]: => Call with -d to detach
2012-08-14T20:45:35+00:00 app[web.1]: from /app/vendor/bundle/ruby/1.9.1/gems/railties-3.2.6/lib/rails/engine.rb:587:in `block in <class
:Engine>'
2012-08-14T20:45:35+00:00 app[web.1]: => Rails 3.2.6 application starting in production on http://0.0.0.0:13851
2012-08-14T20:45:35+00:00 app[web.1]: Exiting
2012-08-14T20:45:35+00:00 app[web.1]: /app/config/initializers/devise.rb:3:in `<top (required)>': uninitialized constant Devise (NameError)
2012-08-14T20:45:35+00:00 app[web.1]: from /app/vendor/bundle/ruby/1.9.1/gems/railties-3.2.6/lib/rails/initializable.rb:30:in `instance_exec'
2012-08-14T20:45:35+00:00 app[web.1]: from /app/vendor/bundle/ruby/1.9.1/gems/railties-3.2.6/lib/rails/initializable.rb:55:in `block in run_initializers'
2012-08-14T20:45:35+00:00 app[web.1]: from /app/vendor/bundle/ruby/1.9.1/gems/railties-3.2.6/lib/rails/application.rb:136:in `initialize!'
2012-08-14T20:45:35+00:00 app[web.1]: from /app/vendor/bundle/ruby/1.9.1/gems/railties-3.2.6/lib/rails/engine.rb:587:in `each'
2012-08-14T20:45:35+00:00 app[web.1]: from /app/vendor/bundle/ruby/1.9.1/gems/railties-3.2.6/lib/rails/initializable.rb:54:in `run_initializers'
2012-08-14T20:45:35+00:00 app[web.1]: from /app/vendor/bundle/ruby/1.9.1/gems/railties-3.2.6/lib/rails/initializable.rb:30:in `run'
2012-08-14T20:45:35+00:00 app[web.1]: from /app/vendor/bundle/ruby/1.9.1/gems/railties-3.2.6/lib/rails/initializable.rb:54:in `each'
2012-08-14T20:45:35+00:00 app[web.1]: from /app/vendor/bundle/ruby/1.9.1/gems/railties-3.2.6/lib/rails/engine.rb:588:in `block (2 levels) in <class:Engine>'
2012-08-14T20:45:35+00:00 app[web.1]: from /app/config.ru:4:in `require'
2012-08-14T20:45:35+00:00 app[web.1]: from /app/vendor/bundle/ruby/1.9.1/gems/railties-3.2.6/lib/rails/railtie/configurable.rb:30:in `method_missing'
2012-08-14T20:45:35+00:00 app[web.1]: from /app/config.ru:4:in `block in <main>'
2012-08-14T20:45:35+00:00 app[web.1]: from /app/config/environment.rb:5:in `<top (required)>'
2012-08-14T20:45:35+00:00 app[web.1]: from /app/vendor/bundle/ruby/1.9.1/gems/rack-1.4.1/lib/rack/builder.rb:51:in `initialize'
2012-08-14T20:45:35+00:00 app[web.1]: from /app/config.ru:1:in `new'
2012-08-14T20:45:35+00:00 app[web.1]: from /app/vendor/bundle/ruby/1.9.1/gems/rack-1.4.1/lib/rack/builder.rb:40:in `eval'
2012-08-14T20:45:35+00:00 app[web.1]: from /app/vendor/bundle/ruby/1.9.1/gems/rack-1.4.1/lib/rack/builder.rb:51:in `instance_eval'
2012-08-14T20:45:35+00:00 app[web.1]: from /app/config.ru:1:in `<main>'
2012-08-14T20:45:35+00:00 app[web.1]: from /app/vendor/bundle/ruby/1.9.1/gems/rack-1.4.1/lib/rack/server.rb:301:in `wrapped_app'
2012-08-14T20:45:35+00:00 app[web.1]: from /app/vendor/bundle/ruby/1.9.1/gems/rack-1.4.1/lib/rack/server.rb:200:in `app'
2012-08-14T20:45:35+00:00 app[web.1]: from /app/vendor/bundle/ruby/1.9.1/gems/railties-3.2.6/lib/rails/commands/server.rb:46:in `app'
2012-08-14T20:45:35+00:00 app[web.1]: from /app/vendor/bundle/ruby/1.9.1/gems/rack-1.4.1/lib/rack/builder.rb:40:in `parse_file'
2012-08-14T20:45:35+00:00 app[web.1]: from /app/vendor/bundle/ruby/1.9.1/gems/rack-1.4.1/lib/rack/server.rb:252:in `start'
2012-08-14T20:45:35+00:00 app[web.1]: from /app/vendor/bundle/ruby/1.9.1/gems/railties-3.2.6/lib/rails/commands/server.rb:70:in `start'
2012-08-14T20:45:35+00:00 app[web.1]: from /app/vendor/bundle/ruby/1.9.1/gems/railties-3.2.6/lib/rails/commands.rb:50:in `<top (required)>'
2012-08-14T20:45:35+00:00 app[web.1]: from script/rails:6:in `require'
2012-08-14T20:45:35+00:00 app[web.1]: from /app/vendor/bundle/ruby/1.9.1/gems/railties-3.2.6/lib/rails/commands.rb:55:in `block in <top (required)>'
2012-08-14T20:45:35+00:00 app[web.1]: from /app/vendor/bundle/ruby/1.9.1/gems/railties-3.2.6/lib/rails/commands.rb:50:in `tap'
2012-08-14T20:45:35+00:00 app[web.1]: from script/rails:6:in `<main>'
2012-08-14T20:45:37+00:00 heroku[web.1]: Process exited with status 1
2012-08-14T20:45:37+00:00 heroku[web.1]: State changed from starting to crashed
2012-08-14T20:46:33+00:00 heroku[router]: Error H10 (App crashed) -> GET sleepy-sands-3221.herokuapp.com/ dyno= queue= wait= service= status=503 bytes=
2012-08-14T20:46:34+00:00 heroku[router]: Error H10 (App crashed) -> GET sleepy-sands-3221.herokuapp.com/favicon.ico dyno= queue= wait= service= status=503 bytes=