The generated code doesn't explicitly have network tables support built in. It generates a class for your pipeline that has methods where you can retrieve the results. That's documented here:
http://wpilib.screenstepslive.com/s/...code-from-grip
with a sample program in Java in the next article after that.
There is also a prebuilt Raspberry PI version of opencv and network tables available. We're planning on putting together a few sample programs that you can use as a starting point for Raspberry PI programs.
Check out this article, and look at ScreenSteps in a few days and we'll have the sample programs and instructions posted.
There is also a pure Python version of network tables developed by the robotpy guys. It's here:
https://github.com/robotpy if you have all the other pieces already.