Fully dynamic d by opDotExp overloading

[BCS]

Hello Steven,


> Also, I don't think the requirement for this feature needs to be for
> the  arguments to be templated, it should be sufficient to have a
> single string  template argument.  This way, you can overload opDotExp
> functions via  argument lists.

split the difference and allow either (but not both):

R opDotExp(char[] name)(ArgList)
R opDotExp(char[] name, T...)(T)