Author: Daniel Neis Araujo
MDL-50834 gradebook: Add help text and link to xml grade import
http://git.moodle.org/gw?p=moodle.git;a=commit;h=9de0c8308694b99ccd2b5f154bbb7671472e7be8
http://github.com/moodle/moodle/commit/9de0c8308694b99ccd2b5f154bbb7671472e7be8
+ 3.0 en [fileurl_help,gradeimport_xml]
+ 3.0 en [importxml,gradeimport_xml]
+ 3.0 en [importxml_help,gradeimport_xml]
+ 3.0 en [importxml_link,gradeimport_xml]
+ 3.0 en [importcsv_link,core_grades]