play20-multiproject/ The root project aggregates submodule and subplay
+- submodule/ A simple scala project
| +- build.sbt Defines submodule project settings
| +- ...
+- subplay/ A normal play2.0 project depends on submodule
| +- build.sbt Defines subplay project settings
| +- ...
+- project/
+- Build.scala Defines the multiple project structure
+- plugins.sbt Defines plugin settings
$ sbt
> project subplay
[subplay] $ run