Let's kill 80bit real at CTFE

[Stefan Koch via Digitalmars-d]

Hi,

In short 80bit real are a real pain to support cross-platform.
emulating them in software is prohibitively slow, and more 
importantly hard to get right.
64bit floating-point numbers are supported on more architectures 
and are much better supported.
They are also trivial to use at ctfe.
I vote for killing the 80bit handling at constant folding.

Destroy!