thread support compiled in the C++ runtime

@stonecracker

No idea what the current status is. My one thought is that we should have a default C++11 (or newer) stdlib that just works out of the box. No need to build a custom GCC with pthreads or anything like that.

I don't particularly care how it works internally, so long as it works well.

Preferably, it'll be stable too so it won't cause any compatibility issues later. I remember dealing with issues on Linux where *.so's and apps all had to be compiled with the same GCC version. That's rather restrictive.

Hans