Add missing doc blocks to wp-admin/includes/*.

Fix some egregious uses of tabbing.
Some functions can simply return `apply_filters(...)` instead of setting a variable that is immediately returned.

See #32444.

Built from https://develop.svn.wordpress.org/trunk@32654


git-svn-id: http://core.svn.wordpress.org/trunk@32624 1a063a9b-81f0-0310-95a4-ce76da25c4cd

wp-admin/network/users.php

@@ -16,6 +16,10 @@ if ( ! is_multisite() )
 if ( ! current_user_can( 'manage_network_users' ) )
 	wp_die( __( 'You do not have permission to access this page.' ), 403 );
 
+/**
+ *
+ * @param array $users
+ */
 function confirm_delete_users( $users ) {
 	$current_user = wp_get_current_user();
 	if ( ! is_array( $users ) || empty( $users ) ) {