Support exclusive access to exit code, output and error streams

[ganapatib]

Problem

Running the following code: Jash jash = Jash.start("docker", "version").withAnyExitCode(), I want to access the exit code, stdout and std error streams to provide helpful information to the user for the next steps. For example, if the error output contains permission denied, the user needs to use sudo. If it contains a connection error, the user needs to start the Docker daemon. Currently, I can only access one of them, and invoking anything else would throw a Stream closed exception.

Right now, my workaround is to also search for strings in the output if the command ran successfully. If this is available, I would just do exitCode == 0.