added tests for sharp7 client

Sharp7.Tests/ServerTestBase.cs

@@ -0,0 +1,25 @@
+using System;
+using System.Linq;
+using Shouldly;
+
+namespace Sharp7.Tests
+{
+    public class ServerTestBase : IDisposable
+    {
+        private readonly S7Server server;
+        protected readonly string Localhost = "127.0.0.1";
+        public ServerTestBase()
+        {
+            server = new S7Server();
+            var rc = server.StartTo(Localhost);
+            rc.ShouldBe(0);
+        }
+
+        public S7Server Server => server;
+
+        public void Dispose()
+        {
+            server.Stop();
+        }
+    }
+}