Add offsetof(), improve comments.
Add basic sys/types.h; separate size_t definition out into ux/size.h; add ux/fixedtypes.h; split UX-targeted vs hosted code in tests with smarter Makefile rules.
Merge branch 'master' of 192.168.1.241:include
Add sys/types compilation test; add ux/darwin/types.h; add architecture switch to ux/fixedtypes.h.