Adding map_code()
Moving scope_size() to scope.h
Managing region and offset during ICG
Making get_place() return self->place if given -1

Useful for iters
Removing DIRECT_DECL2 from code_generate()

Only seen in function declarations which are ignored.
Adding append_code macro
Handling concatenation of code where needed

Heh, can't rely on the default concatenation when there are only certain
subtrees which need to be appended. Then must skip over default
concatenation to scope exit handling, an actually valid use case for a
label and goto pair. Also handling most boolean expressions.