Add support for locating Visual Studio Build Tools without an installation of the IDE

[resiina]

I have only installed Visual Studio Build Tools, not the IDE itself, on a machine that automatically builds projects using the build tools. I'd like to be able to use this to find the Visual Studio Build Tools installation so that I would not need to change the path whenever I update the build system to a newer version of Visual Studio Build Tools.

Steps to reproduce issue:

• Execute vswhere.exe on a machine that doesn't have Visual Studio IDE installed on it, just Visual Studio Build Tools

Expected behaviour:

• vswhere.exe correctly locates the Visual Studio Build Tools directory, just like it does with an installation of Visual Studio IDE

Actual behaviour:

• vswhere.exe does not locate any Visual Studio Build Tools installations

[heaths]

This is already supported. Please see #8. Basically,

vswhere -products *

This will find any product. By default, this was only meant to find instances of Visual Studio. Build Tools does not contain all the same features as Visual Studio.

[daniol]

I use the following to get the installation path:
vswhere -latest -products Microsoft.VisualStudio.Product.BuildTools -property installationPath