added docs about build automation tool

docs/internals/automation.md

+Automation
+==========
+
+There are some tasks that are done automatically when working on Yii:
+
+- Generation of the classmap `classes.php` located under the framework root directory.
+  Run `./build/build classmap` to generate it.
+
+- Generation of the `@property` annotations in class files that describe properties introduced by getters and setters.
+  Run `./build/build php-doc/property` to update them.
+
+- Fixing of code style and other minor issues in phpdoc comments.
+  Run `./build/build php-doc/fix` to run the command.
+  Check the changes before you commit them as there may be unwanted changes because the command is not perfect.
+  You may use `git add -p` to review the changes.

framework/classes.php

@@ -200,6 +200,7 @@ return [
   'yii\rbac\Item' => YII_PATH . '/rbac/Item.php',
   'yii\rbac\ManagerInterface' => YII_PATH . '/rbac/ManagerInterface.php',
   'yii\rbac\Permission' => YII_PATH . '/rbac/Permission.php',
+  'yii\rbac\PhpManager' => YII_PATH . '/rbac/PhpManager.php',
   'yii\rbac\Role' => YII_PATH . '/rbac/Role.php',
   'yii\rbac\Rule' => YII_PATH . '/rbac/Rule.php',
   'yii\requirements\YiiRequirementChecker' => YII_PATH . '/requirements/YiiRequirementChecker.php',