mixin not evaluated during doc generation

[Morusaka]

Jarrett Billingsley Wrote:

> It might or might not make you feel better, but this has already been
> reported.  Twice.
> 
> http://d.puremagic.com/issues/show_bug.cgi?id=648
> http://d.puremagic.com/issues/show_bug.cgi?id=2420
> 
> I wonder if the second should be marked as a dup of the first..

Ooops, thank you Jarrett! Sorry I didn't check reported bugs.
I hope this will be fixed with the next relases.

Luca.