Prepend the Python path for Windows for overriding

lib/exe.js

@@ -471,8 +471,8 @@ function _getNodeCompiler(nodeFileDir, nodeConfigureArgs, nodeMakeArgs, nodeVCBu
           var newEnv = process.env
 
           if (isPy !== "python") {
-            // add the dir of the suposed python exe to path
-            newEnv.path = process.env.PATH + ";" + path.dirname(isPy)
+            // add the dir of the supposed python exe to path
+            newEnv.path = path.dirname(isPy) + ";" + process.env.PATH
           }
 
           if (!nodeVCBuildArgs || !nodeVCBuildArgs.length) {