PHPCS fixes

cron-control.php

 <?php
-
 /**
  * Plugin Name: Cron Control
  * Plugin URI: https://vip.wordpress.com/
@@ -15,7 +14,7 @@
 namespace Automattic\WP\Cron_Control;
 
 // Load basics needed to instantiate plugin.
-require __DIR__ . '/includes/abstract-class-singleton.php';
+require __DIR__ . '/includes/class-singleton.php';
 
 // Instantiate main plugin class, which checks environment and loads remaining classes when appropriate.
 require __DIR__ . '/includes/class-main.php';

includes/abstract-class-singleton.php → includes/class-singleton.php

 <?php
+/**
+ * Abstract singleton for plugin's main classes
+ *
+ * @package a8c_Cron_Control
+ */
 
 namespace Automattic\WP\Cron_Control;
 
+/**
+ * Singleton Class
+ */
 abstract class Singleton {
 	/**
 	 * Class instance
+	 *
+	 * @var array
 	 */
 	private static $__instances = array();
 
+	/**
+	 * Instantiate the class
+	 *
+	 * @return self
+	 */
 	public static function instance() {
 		$caller = get_called_class();
 
@@ -20,6 +35,9 @@ abstract class Singleton {
 		return self::$__instances[ $caller ];
 	}
 
+	/**
+	 * Singleton constructor
+	 */
 	protected function __construct() {}
 
 	/**