No need for version expression is a lie

[Richard (Rikki) Andrew Cattermole]

There is an alternative solution which would be much simpler.

If the scope for which a static assert is located, does not contribute 
towards symbols that get used and another is found, it won't fire.

I.e.

```d
void func() {
	static assert(false);
}
```

As long as you don't call func, it won't fire.

Same goes for:

```d
module binding.b;

version(Windows) {
	extern export void func();

} else {
	static assert(0, "Unimplemented");
}

module binding.a;

void func() {
}
```

There would need to be a way to be stricter and go back to the way we 
have it now via cli. But as far as making porting easier? Yeah it can't 
be beat.