Don't show button to export certificates to PDF - refs BT#9237

Conflicts:
	main/gradebook/lib/be/category.class.php

certificates/index.php

@@ -19,8 +19,8 @@ $certificate = new Certificate($_GET['id']);
 switch ($action) {
     case 'export':
         if (
-            api_is_student() &&
-            api_get_configuration_value('hide_certificate_export_link_students')
+            api_get_configuration_value('hide_certificate_export_link') ||
+            (api_is_student() && api_get_configuration_value('hide_certificate_export_link_students'))
         ) {
             api_not_allowed(true);
         }

main/gradebook/gradebook_display_certificate.php

@@ -180,7 +180,7 @@ echo Display::url(get_lang('GenerateCertificates'), $url, array('class' => 'btn
 $url = api_get_self().'?action=delete_all_certificates'.'&'.api_get_cidReq().'&cat_id='.$cat_id.'&filter='.$filterOfficialCode;
 echo Display::url(get_lang('DeleteAllCertificates'), $url, array('class' => 'btn btn-default'));
 
-if (count($certificate_list) > 0) {
+if (count($certificate_list) > 0 && !api_get_configuration_value('hide_certificate_export_link')) {
     $url = api_get_self().'?action=export_all_certificates'.'&'.api_get_cidReq().'&cat_id='.$cat_id.'&filter='.$filterOfficialCode;
     echo Display::url(get_lang('ExportAllCertificatesToPDF'), $url, array('class' => 'btn btn-default'));
 }

main/gradebook/lib/be/category.class.php

@@ -1860,8 +1860,8 @@ class Category implements GradebookItem
                 );
 
                 if (
-                    api_is_student() &&
-                    api_get_configuration_value('hide_certificate_export_link_students')
+                    api_get_configuration_value('hide_certificate_export_link') ||
+                    (api_is_student() && api_get_configuration_value('hide_certificate_export_link_students'))
                 ) {
                     $exportToPDF = null;
                 }

main/install/configuration.dist.php

@@ -328,3 +328,5 @@ $_configuration['system_stable']     = NEW_VERSION_STABLE;
 //$_configuration['show_session_description'] = false;
 // Hide only for students the link to export certificates to PDF 
 //$_configuration['hide_certificate_export_link_students'] = false;
+// Hide for all user roles the link to export certificates to PDF 
+//$_configuration['hide_certificate_export_link'] = false;