Fixed a critical bug in the runtime, where _d_allocmemoryT would mark the memory block as having pointers (for scanning) opposite of what it should. So pointers would not be seen and freed. Should fix a bunch of regressions with AAs.

module aa2;

void main()
{
    long[float] aa;
    long* p = 2.0f in aa;
    assert(!p);
    aa[4f] = 23;
    p = 4f in aa;
    assert(p);
    assert(*p == 23);
}