More tests. Broken.

Thinking twice, I think it can be fun to collaborate on this at a distance. :smirk: 

Here are a few broken tests - a few for the parser, a few for the interpreter. I found out that there are two print operators in Forth. A simple dot (.) pops the stack and prints the result, while .S prints the top of the stack without any side effect.

Of course you're going to be drunkish and partied at RailsConf, which only makes the entire exercise more interesting...