[svn r354] Fix the regressions between [346] and [353] by making constructors and destructors outside classes fatal errors. Fix tests makefile and add minimize to gc.d.

module complex3;

void main()
{
    cfloat c1 = 1f + 0i;
    cfloat c2 = 0f + 0i;
    c2 += 1f + 0i;
    //assert(c1 == c2);
}