Helpful error message if VS C++ compiler toolset is missing or VS is not installed, also added option to override VCVarsAll.bat file location (and forgo search strategy) with any specific file if the VS C++ compiler toolset has been installed in an unorthodox manner ;)
Helpful error message if VS C++ compiler toolset is missing or VS is not installed, also added option to override VCVarsAll.bat file location (and forgo search strategy) with any specific file if the VS C++ compiler toolset has been installed in an unorthodox manner ;)

deplinenoise/tundra,bmharper/tundra,deplinenoise/tundra,bmharper/tundra,deplinenoise/tundra,bmharper/tundra,bmharper/tundra