The stub .java classes generated by rmic should be committed to the repo.
It removes a dependency on rmic and simplifies the build.

The stubs include:
- javax/management/remote/rmi/RMIConnectionImpl
- javax/management/remote/rmi/RMIServerImpl
- sun/rmi/server/Activation$ActivationSystemImpl
- com/sun/jndi/rmi/registry/ReferenceWrapper

The generated .java files will be edited to remove compiler warnings.