Added HXCPP support for Visual Studio Community 2017

Hello everyone!

I just setup a new Windows system using Visual Studio Community 2017, and noticed that HXCPP (even on dev) was not able to automatically set up the variables needed to build.

The development version should now have support for VS Community 2017:

If anyone else uses Visual Studio Community 2017, or uses the standard version of Visual Studio 2017, and has any issues or needs tweaks, please let me know so we can help support that inside HXCPP :smile: