Change the numbering of static ctors/dtors to be module based instead of being global. This fixes #210 by making sure that the static ctor always gets the same number, regardless of the order of the modules given at the command line.

// testcase from bug #199

struct Color {
    uint c;

}

struct Vertex {
    Color c;
}

void main() {
    Color c = {0xffffffff};

    auto v = Vertex(c);

    assert(v.c.c == 0xffffffff);  // fails in LDC
}