This patch adds support for the ROT_THREE and ROT_FOUR
interpreter instructions. I don't know why they are
The ROT_THREE instruction is used by the interpreter
while interpreting the following piece of code:
return (32 < 10 < 126)
I don't have an example of code using the ROT_FOUR
instruction, but since it's trivial, I think it's worth
including in the code.