Supplemental control statements for scripting


Here's for, break and continue. I really would appreciate a code review from Ivan on this one just to make sure I'm not doing anything stupid. The big red chunk is me refactoring assignment into a function (so it can be called inside the for statement parser).

This implements "for", "break" and "continue" using the existing control
structures inside cs_parser.cpp. They are, after all, just ways of
paraphrasing other control statements. The for statement takes the usual
parameters, but they can be omitted. One caveat is that the for
statement cannot include variable declarations (e.g. int x = 0) for the
initialisation part, only assignments.