Remove some redundancy from the DValue hierarchy: all subclasses had a 'type' field and identical implementations of virtual function getType(). Move these to DValue itself, and make getType() non-virtual.

import tango.io.Console;
void main()
{
    Cout("getting name std").newline;
    Cerr("getting name err").newline;
    auto s = Cin.get();
    Cout("putting name").newline;
    Cout (s).newline;
}