My vibe-d test app is crashing on Windows

[Steve]

The app is just a test echo server. JSON sent in the body of a 
POST request is echoed back to the client. On Pop!_OS it works 
fine but on Windows it responds, there's a delay of about 10 
seconds and then it crashes with the error:

```
Error Program exited with code -1073741819
```

Here's the code:
```d
import vibe.vibe;
import std.json, std.stdio;

void main() {
	auto settings = new HTTPServerSettings;
	settings.port = 8080;
	settings.bindAddresses = ["::1", "127.0.0.1"];

     auto router = new URLRouter;
     router.get("*", serveStaticFiles("public/"));
     router.post("/", &onPost);

	auto listener = listenHTTP(settings, router);
	scope (exit) { listener.stopListening(); }

	logInfo("App listening at http://127.0.0.1:8080/");
	runApplication();
}

static string handlePost(string req) {
     return req;
}

void onPost(HTTPServerRequest req, HTTPServerResponse res) {
     try {
         auto jsr = async(&handlePost, 
req.json.toString()).getResult();
         res.contentType("application/json; charset=utf-8");
         res.writeBody(jsr);
     } catch (Exception e) {
         res.contentType("text/plain; charset=utf-8");
         res.writeBody(e.msg);
     }
}
```

Also when you launch/build the app with dub there's a shed load 
of deprecation warnings, e.g.:
```
\Local\dub\packages\vibe-d-0.9.5\vibe-d\stream\vibe\stream\wrapper.d(334,23): Deprecation: reference to local variable `this` assigned to non-scope parameter `bytes` calling `writeToStream`
```

I'm a D newbie so it's quite possibly something I'm doing wrong 
...