Tweaks to VSTool source and executable for compatibility with VS 2017

indra/tools/vstool/main.cs

@@ -556,7 +556,7 @@ namespace VSTool
                         break;
 
                     case "12.00":
-                        version = "VC120";
+                        version = "VC150";
                         break;
 
                     default:
@@ -603,6 +603,10 @@ namespace VSTool
                     progid = "VisualStudio.DTE.12.0";
                     break;
 
+                case "VC150":
+                    progid = "VisualStudio.DTE.15.0";
+                    break;
+
                 default:
                     throw new ApplicationException("Can't handle VS version: " + version);
             }