redirecting standard error for max causes max to hang

when trying to install integration. Try getting error from standard
output instead

Author: vkovec

Assets/FbxExporters/Editor/InstallIntegration.cs

@@ -627,7 +627,7 @@ public static int InstallMaxPlugin(string maxExe){
                 myProcess.StartInfo.WindowStyle = System.Diagnostics.ProcessWindowStyle.Hidden;
                 myProcess.StartInfo.CreateNoWindow = true;
                 myProcess.StartInfo.UseShellExecute = false;
-                myProcess.StartInfo.RedirectStandardError = true;
+                myProcess.StartInfo.RedirectStandardOutput = true;
 
                 myProcess.StartInfo.Arguments = string.Format("-q -silent -mxs \"{0}\"", installScript);
 
@@ -649,7 +649,7 @@ public static int InstallMaxPlugin(string maxExe){
 
                 // print any errors
                 if(ExitCode != 0){
-                    string stderr = myProcess.StandardError.ReadToEnd();
+                    string stderr = myProcess.StandardOutput.ReadToEnd();
                     if(!string.IsNullOrEmpty(stderr)){
                         Debug.LogError(string.Format("3ds Max installation error (exit code: {0}): {1}", ExitCode, stderr));
                     }