Execute SQL statement at cursor location (#412)

* Stage changes to other machine

* Parse sql statement from script document

* Fix a few typos and minor changes

* Fix bug

src/Microsoft.SqlTools.ServiceLayer/QueryExecution/Contracts/ExecuteRequests/ExecuteDocumentStatementRequest.cs

@@ -0,0 +1,32 @@
+//
+// 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.Hosting.Protocol.Contracts;
+
+namespace Microsoft.SqlTools.ServiceLayer.QueryExecution.Contracts.ExecuteRequests
+{
+    /// <summary>
+    /// Parameters for executing a query from a document open in the workspace
+    /// </summary>
+    public class ExecuteDocumentStatementParams : ExecuteRequestParamsBase
+    {
+        /// <summary>
+        /// Line in the document for the location of the SQL statement
+        /// </summary>
+        public int Line { get; set; }
+
+        /// <summary>
+        /// Column in the document for the location of the SQL statement
+        /// </summary>
+        public int Column { get; set; }        
+    }
+    
+    public class ExecuteDocumentStatementRequest
+    {
+        public static readonly 
+            RequestType<ExecuteDocumentStatementParams, ExecuteRequestResult> Type = 
+            RequestType<ExecuteDocumentStatementParams, ExecuteRequestResult>.Create("query/executedocumentstatement");
+    }
+}