Changed some hardcoded offset/alignment for classes in DMD, broke offsets for 64bits. Changed ClassInfo generation to no longer access the default initializer of ClassInfo, fixes problems with index mismatch.

module classes10;

class C
{
    int i;
    override char[] toString()
    {
        return "foobar";
    }
}

void main()
{
    Object o = new C;
    char[] s = o.toString();
    assert(s == "foobar");
}