Docs: Improve the DocBlock summary and add a missing initial @since version for WP_Admin_Bar::add_node().

See #32246. See #35986.

Built from https://develop.svn.wordpress.org/trunk@36833


git-svn-id: http://core.svn.wordpress.org/trunk@36800 1a063a9b-81f0-0310-95a4-ce76da25c4cd

wp-includes/class-wp-admin-bar.php

@@ -96,9 +96,11 @@ class WP_Admin_Bar {
 	}
 
 	/**
-	 * Add a node to the menu.
+	 * Adds a node to the menu.
 	 *
+	 * @since 3.1.0
 	 * @since 4.5.0 Added the ability to pass 'lang' and 'dir' meta data.
+	 * @access public
 	 *
 	 * @param array $args {
 	 *     Arguments for adding a node.