Feature/10371 osx proxy issue

As reported by users (Ross Stuart) the script repository is currently failing on OSX with the message:

Connection and request failed . Unkown:Timeout: connect timed out: 198.74.56.37:80

This should not be happening and needs fixing ASAP.
The clean Windows debug build has failed when compiling this file. I think it is actually just because that build also turns off the use of pre-compiled headers and not the fact that it is debug build. The errors are odd but it looks like they just need the extra includes: 

```cpp
// std
#include <sstream>
// windows
#include <windows.h>
```

The ```<windows.h>``` one must be before ```<Winhttp.h>```.