groovy support

Proof of concept groovy support - just shows your framework will work with groovy as well as java
(java syntax is for the most part valid groovy, so the helloworld example is valid as a groovy file)


Oh, just saw the `if (offset == 0)`. I guess that works for linear reads, but it still gives the wrong impression that reads can be assumed to be linear. As this is a sample filesystem, simple is better, so I stand by the suggestion to leave the `ps aux` taken at start time only.