Why not print member function attributes (`const`, `immutable`, etc) when the argument is a type?

```d
struct S { void foo() const {} }
pragma(msg, __traits(getFunctionAttributes,        S.foo ));  // tuple("const")
pragma(msg, typeof(S.foo));  // const void()
pragma(msg, __traits(getFunctionAttributes, typeof(S.foo)));  // tuple(), inconsistent
```