Docs: Add a description and example to the hook docs for the `navigation_markup_template` filter, introduced in [33714].

Since the value of the filter is passed through `sprintf()` it's important to note that any filtered output needs to contain the expected specifiers.

See #31315.

Built from https://develop.svn.wordpress.org/trunk@33717


git-svn-id: http://core.svn.wordpress.org/trunk@33684 1a063a9b-81f0-0310-95a4-ce76da25c4cd

wp-includes/link-template.php

@@ -2426,10 +2426,19 @@ function _navigation_markup( $links, $class = 'posts-navigation', $screen_reader
 	/**
 	 * Filter the navigation markup template.
 	 *
+	 * Note: The filtered template HTML must contain specifiers for the navigation
+	 * class (%1$s), the screen-reader-text value (%2$s), and placement of the
+	 * navigation links (%3$s):
+	 *
+	 *     <nav class="navigation %1$s" role="navigation">
+	 *         <h2 class="screen-reader-text">%2$s</h2>
+	 *         <div class="nav-links">%3$s</div>
+	 *     </nav>
+	 *
 	 * @since 4.4.0
 	 *
-	 * @param string $template The default template
-	 * @param string $class The class passed by the calling function.
+	 * @param string $template The default template.
+	 * @param string $class    The class passed by the calling function.
 	 * @return string Navigation template.
 	 */
 	$template = apply_filters( 'navigation_markup_template', $template, $class );

wp-includes/version.php

@@ -4,7 +4,7 @@
  *
  * @global string $wp_version
  */
-$wp_version = '4.4-alpha-33716';
+$wp_version = '4.4-alpha-33717';
 
 /**
  * Holds the WordPress DB revision, increments when changes are made to the WordPress DB schema.