Add Scripter class and use it in the ScriptingService (#286)

* Initial scripting commit

* Fix the script CREATE integration test

* Use language service binding queue for scripting

* Update scripting service to have methods for each operation

* Add scripter class

* Fix build break.

* Fix a few bugs

* Use scripter class instead of PeekDefinition class.

* Fix scripting test break

* Fix header incorrectly saying file is generated.

* Add localization tests to address a large block of code not covered by automation.

* Moving system usings to top of using list

src/Microsoft.SqlTools.ServiceLayer/Metadata/MetadataService.cs

@@ -76,7 +76,7 @@ namespace Microsoft.SqlTools.ServiceLayer.Metadata
                     ReadMetadata(sqlConn, metadata);
                 }
 
-                await requestContext.SendResult(new MetadataQueryResult()
+                await requestContext.SendResult(new MetadataQueryResult
                 {
                     Metadata = metadata.ToArray()
                 });