MDL-36017 Fields numsections, hiddensections and coursedisplay are now format-specific options

- Fields added to format_legacy as default course format options;
- Upgrade script copies fields values from table course to course_format_options;
- Fields removed from table course;
- Fields removed from edit course form;
- Since front-page course has a 'numsections' setting, format_site defines it as it's option;
- Removed accessing those fields in core code unless we know that format supports them and in this
  case instead of $course = $DB->get_record('course'); we use:
  $course = course_get_format($courseorid)->get_course(); This way all format-specific options
  are added to the $course object

lib/db/install.php

@@ -86,6 +86,10 @@ function xmldb_main_install() {
         $newsite->id = $DB->insert_record('course', $newsite);
         define('SITEID', $newsite->id);
     }
+    // set the field 'numsections'. We can not use format_site::update_format_options() because
+    // the file is not loaded
+    $DB->insert_record('course_format_options', array('courseid' => SITEID, 'format' => 'site',
+        'sectionid' => 0, 'name' => 'numsections', 'value' => $newsite->numsections));
     $SITE = get_site();
     if ($newsite->id != $SITE->id) {
         throw new moodle_exception('generalexceptionmessage', 'error', '', 'Unexpected new site course id!');