A cleaner implementation of <.

This is clearly an unbelievably inefficient way of doing this. But them's the breaks.
Add a method for getting random numbers.
Alter particles to directly know the form in which they are pushed to the stack.

This will allow (native) operators which want to do this transformation without pushing
items to the stack to do so.
Some more list manipulation methods, along with some fixes where we were pushing
Ints on to the stack (argh!).