Add tests to improve code coverage (#187)

* DbColumn and ReliableConnection tests

* More retry connection tests

* More tests

* Fix broken peek definition integration tests

* Fix test bug

* Add a couple batch tests

* Add some more tests

* More tests for code coverage.

* Validation and Diagnostic tests

* A few more tests

* A few mote test changes.

* Update file path tests to run on Windows only

test/Microsoft.SqlTools.ServiceLayer.Test/Utility/SrTests.cs

@@ -0,0 +1,27 @@
+//
+// Copyright (c) Microsoft. All rights reserved.
+// Licensed under the MIT license. See LICENSE file in the project root for full license information.
+//
+
+using Microsoft.SqlTools.ServiceLayer;
+using Xunit;
+
+namespace Microsoft.SqlTools.Test.Utility
+{
+    public class SrTests
+    {
+        /// <summary>
+        /// Add and remove and item in a LongList
+        /// </summary>
+        [Fact]
+        public void SrPropertiesTest()
+        {
+            Assert.NotNull(new SR());
+            Assert.NotNull(SR.QueryServiceSubsetBatchNotCompleted);
+            Assert.NotNull(SR.QueryServiceFileWrapperWriteOnly);
+            Assert.NotNull(SR.QueryServiceFileWrapperNotInitialized);
+            Assert.NotNull(SR.QueryServiceColumnNull);
+            Assert.NotNull(new SR.Keys());   
+        }
+    }
+}