Restructure packaging directories. Move C# bindings, minor compilation fix.

src/bindings/csharp/SocketException.cs

@@ -0,0 +1,38 @@
+/*
+ * Copyright (c)2013-2020 ZeroTier, Inc.
+ *
+ * Use of this software is governed by the Business Source License included
+ * in the LICENSE.TXT file in the project's root directory.
+ *
+ * Change Date: 2024-01-01
+ *
+ * On the date above, in accordance with the Business Source License, use
+ * of this software will be governed by version 2.0 of the Apache License.
+ */
+/****/
+
+using System;
+
+namespace ZeroTier
+{
+	/// <summary>Exception class for ZeroTier service and low-level socket errors</summary>
+	public class SocketException : Exception
+	{
+		public SocketException(int _serviceErrorCode)
+		: base(String.Format("ServiceErrorCode={0} (See Constants.cs for error code meanings)", _serviceErrorCode))
+		{
+			ServiceErrorCode = _serviceErrorCode;
+		}
+		public SocketException(int _serviceErrorCode, int _socketErrorCode)
+		: base(String.Format("ServiceErrorCode={0}, SocketErrorCode={1} (See Constants.cs for error code meanings)", _serviceErrorCode, _socketErrorCode))
+		{
+			ServiceErrorCode = _serviceErrorCode;
+			SocketErrorCode = _socketErrorCode;
+		}
+		/// <value>High-level service error code. See Constants.cs</value>
+		public int ServiceErrorCode { get; private set; }
+
+		/// <value>Low-level socket error code. See Constants.cs</value>
+		public int SocketErrorCode { get; private set; }
+	}
+}