添加C#sdk

sop-sdk/sdk-csharp/SDKCSharp/Common/IgnoreSign.cs

@@ -0,0 +1,14 @@
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Text;
+
+namespace SDKCSharp.Request
+{
+    /// <summary>
+    /// 元数据，放在属性上面，表示忽略签名
+    /// </summary>
+    sealed class IgnoreSign : Attribute
+    {
+    }
+}