Added websocket base

CryptoExchange.Net/Interfaces/IWebsocket.cs

@@ -0,0 +1,24 @@
+using System;
+using System.Security.Authentication;
+using System.Threading.Tasks;
+
+namespace CryptoExchange.Net.Interfaces
+{
+    public interface IWebsocket
+    {
+        void SetEnabledSslProtocols(SslProtocols protocols);
+
+        event Action OnClose;
+        event Action<string> OnMessage;
+        event Action<Exception> OnError;
+        event Action OnOpen;
+
+        bool IsClosed { get; }
+        bool IsOpen { get; }
+
+        Task<bool> Connect();
+        void Send(string data);
+        void Close();
+        void SetProxy(string host, int port);
+    }
+}

CryptoExchange.Net/Interfaces/IWebsocketFactory.cs

@@ -0,0 +1,7 @@
+namespace CryptoExchange.Net.Interfaces
+{
+    public interface IWebsocketFactory
+    {
+        IWebsocket CreateWebsocket(string url);
+    }
+}