Include ManagedBatchParser tests to improve code coverage (#793)

* Include ManagedBatchParser test to improve code coverage

* Fix some failing test cases and revert appveyor.yml

test/Microsoft.SqlTools.ManagedBatchParser.IntegrationTests/Utility/FileUtilities.cs

@@ -0,0 +1,20 @@
+using System.IO;
+
+namespace Microsoft.SqlTools.ManagedBatchParser.IntegrationTests.Utility
+{
+    internal class FileUtilities
+    {
+        /// <summary>
+        /// Turns off the read-only attribute for this file
+        /// </summary>
+        /// <param name="fullFilePath"></param>
+        internal static void SetFileReadWrite(string fullFilePath)
+        {
+            if (!string.IsNullOrEmpty(fullFilePath) &&
+                File.Exists(fullFilePath))
+            {
+                File.SetAttributes(fullFilePath, FileAttributes.Normal);
+            }
+        }
+    }
+}