log unhandle exception

shadowsocks-csharp/Data/cn.txt

@@ -101,3 +101,5 @@ Failed to decode QRCode=无法解析二维码
 Failed to update registry=无法修改注册表
 System Proxy On: =系统代理已启用：
 Running: Port {0}=正在运行：端口 {0}
+Unexpect error, shadowsocks will be exit. Please report to=非预期错误，Shadowsocks将退出。请提交此错误到
+ 

shadowsocks-csharp/Program.cs

@@ -55,12 +55,18 @@ namespace Shadowsocks
             }
         }
 
+        private static int exited = 0;
         private static void CurrentDomain_UnhandledException(object sender, UnhandledExceptionEventArgs e)
         {
-            Logging.Error(e.ExceptionObject?.ToString());
-            MessageBox.Show($"Unexpect error, shadowsocks exited.{Environment.NewLine} {e.ExceptionObject?.ToString()}",
-                "Shadowsocks", MessageBoxButtons.OK, MessageBoxIcon.Error);
-            Application.Exit();
+            if (Interlocked.Increment(ref exited) == 1)
+            {
+                Logging.Error(e.ExceptionObject?.ToString());
+                MessageBox.Show(I18N.GetString("Unexpect error, shadowsocks will be exit. Please report to") +
+                    " https://github.com/shadowsocks/shadowsocks-windows/issues " +
+                    Environment.NewLine + (e.ExceptionObject?.ToString()),
+                    "Shadowsocks Error", MessageBoxButtons.OK, MessageBoxIcon.Error);
+                Application.Exit();
+            }
         }
     }
 }