My cxxversion and stdheaders

 In various bits of code: I’ve been using these headers to solve the “__cplusplus says yeah, but actually compiling says go to hell” problems. Because sometimes the macro tells you one thing and actually trying to preprocess and link makes naughty hand gestures on the systems I encounter.

Finally, I’ve gotten around to sticking these in their own repo.

Which is much nicer than going: “Which project did I last update that in?”