backporting features to D1

[Anders F Bjöšrklund]

Jarrett Billingsley wrote:

> A lot of the things I've seen is people having issues making codebases
> compatible with both D1 and D2, which really _is_ a royal pain.

I tried keeping the same codebase compatible with D1 and D2,
Phobos and Tango, GDC and DMD, and still remain portable too.
(without changing or generating the code with a preprocessor,
and without copying / pasting and replacing "version(linux)")

I don't think I will try that again :-)

--anders