Minor updates for Sammy

I fixed a couple minor issues in the Sammy definitions. There may be other changes required - I haven't tried to be comprehensive, just fixed a few things I noticed were wrong (and needed to be changed for my own code).

I also haven't tried to fix the Sammy tests yet - they won't compile, but I'm not entirely sure I understand what they're doing, and hence I'm not sure how to fix them.