Fix VarDecls for tuples. Closes #99. I've implemented it this way since it doesn't require any changes in the frontend. However, I think having TypeTuple expressed as LLVM struct types would make much more sense and open the door to tuple lvalues.

module bug75;

void func(void delegate() dg)
{
}

void main()
{
    void nested() {
    }
    //func(&nested);
    void delegate() dg = &nested;
}