我正在尝试使用这个很棒的模板来跟踪scala和spray的教程：http://typesafe.com/activator/template/activator-akka-spray
然后我按照Heroku部署的说明进行操作：https://devcenter.heroku.com/articles/getting-started-with-scala
运行命令“ sbt clean compile stage ”时遇到问题，以便在Heroku上准备部署。以下是错误消息：
[info] Loading project definition from /.../activator-akka-spray/project
[info] Set current project to activator-akka-spray (in build file:/.../activator-akka-spray/)
[error] Not a valid command: stage (similar: last-grep, set, last)
[error] Expected '/'
[error] Expected ':'
[error] Not a valid key: stage (similar: state, target, tags)
[error] stage
[error] ^
有没有人遇到过类似的错误？
提前感谢您的帮助。