MDL-32508 course formats: make renderer methods protected

The renderer isn't a public API yet, its just reducing code duplication
and tidying things up. So not making the methods public for other plugins
to abuse. We hope to solve this properly in 2.4

course/format/weeks/renderer.php

@@ -39,7 +39,7 @@ class format_weeks_renderer extends format_section_renderer_base {
      * Generate the starting container html for a list of sections
      * @return string HTML to output.
      */
-    public function start_section_list() {
+    protected function start_section_list() {
         return html_writer::start_tag('ul', array('class' => 'weeks'));
     }
 
@@ -47,7 +47,7 @@ class format_weeks_renderer extends format_section_renderer_base {
      * Generate the closing container html for a list of sections
      * @return string HTML to output.
      */
-    public function end_section_list() {
+    protected function end_section_list() {
         return html_writer::end_tag('ul');
     }
 
@@ -55,7 +55,7 @@ class format_weeks_renderer extends format_section_renderer_base {
      * Generate the title for this section page
      * @return string the page title
      */
-    public function page_title() {
+    protected function page_title() {
         return get_string('weeklyoutline');
     }
 }