Small change to the rig implementation (SharePoint#1267)

Small change to the rig implementation to have comments consistency and TypeScript name update.

Author: estruyf

docs/spfx/toolchain/integrate-gulp-tasks-in-build-pipeline.md

@@ -86,13 +86,13 @@ You can also add this custom task to be executed before or after certain availab
 The SharePoint Framework tasks are available in the default build rig. The build rig is a collection of tasks defined for a specific purpose. In our case, building client-side packages. You can access this default rig using the `build.rig` object and get access to the pre and post task functions:
 
 ```js
-//execute before the typescript subtask
+// execute before the TypeScript subtask
 build.rig.addPreBuildTask(helloWorldTask);
 
-// execute after TypeScript task
+// execute after TypeScript subtask
 build.rig.addPostTypescriptTask(helloWorldTask);
 
-//execute after all tasks
+// execute after all tasks
 build.rig.addPostBuildTask(helloWorldTask);
 ```