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.

module typeinfo11;

void main()
{
    int[4] a;
    TypeInfo ti;
    ti = typeid(typeof(a));
    assert(ti.next() is typeid(int));
    assert(ti.tsize() == 16);
}