我在Heroku上部署了我的第一个应用程序。该应用程序正在运行我做了一些CSS样式，添加了一个gem并添加了一个小部件。推到Heroku后我开始收到这个错误 应用程序错误， 应用程序中发生错误，无法提供您的页面。如果您是应用程序所有者，请查看日志以获取详细信息 我删除了所有更改并删除了宝石，但我仍然遇到同样的错误。 有人可以帮忙吗 这就是我的日志所说的。
应用程序日志
2016-12-19T07:39:21.070388+00:00 app[web.1]: from /app/vendor/bundle/ruby/2.2.0/gems/rack-2.0.1/lib/rack/server.rb:282:in `start'
2016-12-19T07:39:21.070390+00:00 app[web.1]: from /app/vendor/bundle/ruby/2.2.0/gems/railties-5.0.0.1/lib/rails/commands/server.rb:79:in `start'
2016-12-19T07:39:21.070392+00:00 app[web.1]: from /app/vendor/bundle/ruby/2.2.0/gems/railties-5.0.0.1/lib/rails/commands/commands_tasks.rb:90:in `block in server'
2016-12-19T07:39:21.070394+00:00 app[web.1]: from /app/vendor/bundle/ruby/2.2.0/gems/railties-5.0.0.1/lib/rails/commands/commands_tasks.rb:85:in `tap'
2016-12-19T07:39:21.070398+00:00 app[web.1]: from /app/vendor/bundle/ruby/2.2.0/gems/railties-5.0.0.1/lib/rails/commands/commands_tasks.rb:49:in `run_command!'
2016-12-19T07:39:21.070396+00:00 app[web.1]: from /app/vendor/bundle/ruby/2.2.0/gems/railties-5.0.0.1/lib/rails/commands/commands_tasks.rb:85:in `server'
2016-12-19T07:39:21.070400+00:00 app[web.1]: from /app/vendor/bundle/ruby/2.2.0/gems/railties-5.0.0.1/lib/rails/commands.rb:18:in `<top (required)>'
2016-12-19T07:39:21.070402+00:00 app[web.1]: from bin/rails:4:in `require'
2016-12-19T07:39:21.070421+00:00 app[web.1]: from bin/rails:4:in `<main>'
2016-12-19T12:18:12.445785+00:00 heroku[router]: at=error code=H10 desc="App crashed" method=GET path="/" host=bark-sj.herokuapp.com request_id=b19b4989-195e-4dd9-b9d4-be040f005567 fwd="71.75.222.70" dyno= connect= service= status=503 bytes=
2016-12-19T12:18:12.883504+00:00 heroku[router]: at=error code=H10 desc="App crashed" method=GET path="/favicon.ico" host=bark-sj.herokuapp.com request_id=da691f65-a247-4486-be41-5e40a24bf73d fwd="71.75.222.70" dyno= connect= service= status=503 bytes=
2016-12-19T12:19:06.946508+00:00 heroku[router]: at=error code=H10 desc="App crashed" method=GET path="/" host=bark-sj.herokuapp.com request_id=2742ae66-fc1a-41f3-a7a1-34f19d80be2c fwd="71.75.222.70" dyno= connect= service= status=503 bytes=
2016-12-19T12:19:07.336515+00:00 heroku[router]: at=error code=H10 desc="App crashed" method=GET path="/favicon.ico" host=bark-sj.herokuapp.com request_id=b0fb1a59-64b3-4b94-a5d4-cf620e3522b1 fwd="71.75.222.70" dyno= connect= service= status=503 bytes=
2016-12-19T12:19:35.432525+00:00 heroku[router]: at=error code=H10 desc="App crashed" method=GET path="/" host=bark-sj.herokuapp.com request_id=2ec59492-b01c-48bc-85b1-d8cb836429ce fwd="71.75.222.70" dyno= connect= service= status=503 bytes=
2016-12-19T12:19:35.816449+00:00 heroku[router]: at=error code=H10 desc="App crashed" method=GET path="/favicon.ico" host=bark-sj.herokuapp.com request_id=d80af4e9-e11d-4117-a2f0-c03e5a5df940 fwd="71.75.222.70" dyno= connect= service= status=503 bytes=
2016-12-19T12:19:44.824487+00:00 heroku[router]: at=error code=H10 desc="App crashed" method=GET path="/" host=bark-sj.herokuapp.com request_id=ec97a999-1805-4755-b975-fc497ca7f4dc fwd="71.75.222.70" dyno= connect= service= status=503 bytes=
2016-12-19T12:19:45.234548+00:00 heroku[router]: at=error code=H10 desc="App crashed" method=GET path="/favicon.ico" host=bark-sj.herokuapp.com request_id=a5501bea-0322-4053-8b80-9fd4a62e49ac fwd="71.75.222.70" dyno= connect= service= status=503 bytes=