Robospock integration

here goes a PR that adds/fixes robospock integration in your project
that scary build.gradle file, mentioned in this commit https://github.com/pelotasplus/RoboSpockExample/commit/6a8784d04e18f7ec2f5b23b18dd56c49818117d0, was made by @pjakubczyk and he's the one who knows what's going there ;-)