builds but doesn't run yet

Conflicts:
	src/codegen/irgen.h
	src/codegen/irgen/irgenerator.cpp
	src/codegen/unwinding.cpp
	src/core/types.h

Some other merge changes as well

Maybe this was the issue I was running into earlier

Makes the IR much easier to follow.  Also I think the plan will be
to have the cxx unwinder do the refcounting.

(if the variable is defined before then)
otherwise we would try to incref the variable before guards which would fail the rewrite.

(At least, the ones that we referenced statically.)

Amazing that it didn't end up showing up until now.