message: docs: C++ are not auto-selected by Visual Studio anymore
  Its not possible to build Etcher without it. For some reason, the Visual
  Studio Community 2015 installer is not ticking it by default anymore.
  See:
diff: @@ -23,6 +23,9 @@ Prerequisites
  - [Rimraf](https://github.com/isaacs/rimraf)
  - [NSIS v2.51](http://nsis.sourceforge.net/Main_Page) (v3.x won't work)
  - [Visual Studio Community 2015](https://www.microsoft.com/en-us/download/details.aspx?id=48146) (free) (other editions, like Professional and Enterprise, should work too)
  + - Visual Studio 2015 doesn't install C++ by default. You have to rerun the
  + setup, select Modify and then check `Visual C++ -> Common Tools for Visual
  + C++ 2015` (see http://stackoverflow.com/a/31955339)
  - [MinGW](http://www.mingw.org)
  The following MinGW packages are required:
  