Merged in feature/from-pantheon (pull request #16)

code from pantheon

* code from pantheon

wp/wp-content/plugins/wordpress-seo/admin/roles/class-role-manager-factory.php

@@ -0,0 +1,27 @@
+<?php
+/**
+ * WPSEO plugin file.
+ *
+ * @package WPSEO\Admin\Roles
+ */
+
+/**
+ * Role Manager Factory.
+ */
+class WPSEO_Role_Manager_Factory {
+
+	/**
+	 * Retrieves the Role manager to use.
+	 *
+	 * @return WPSEO_Role_Manager
+	 */
+	public static function get() {
+		static $manager = null;
+
+		if ( $manager === null ) {
+			$manager = new WPSEO_Role_Manager_WP();
+		}
+
+		return $manager;
+	}
+}