remodel Context to keep a pointer to the parent
remodel Context to keep a pointer to the parent

This ensures that the parent context can be extended after the child has been constructed (to allow forward references to global definitions)

ArielAbreu/bonsai-c,ArielAbreu/bonsai-c,beni55/bonsai-c,gasman/bonsai-c,gasman/bonsai-c,beni55/bonsai-c,beni55/bonsai-c,ArielAbreu/bonsai-c,gasman/bonsai-c