Porting my Integer Sorting Algorithms to D

[Nordlöw]

I have a couple of self-implemented C++ integer sort algorithms 
lying around in my codebase.

I also have a parallel merge sort on top of them that uses Intel 
TBB to give some
further speedups.
I have tweaked them to also work for floats and doubles, through 
some interesting bit-fiddling tips I found on the net.

Would anybody be interested in reviewing these to give 
suggestions on how to best port it to Phobos?

/Per