used:
http://[hostname]/webservice/rest/server.php?wstoken=[token]&wsfunction=core_enrol_get_enrolled_users&moodlewsrestformat=json&courseid=[idcourse]
used:
http://[hostname]/webservice/rest/server.php?wstoken=[token]&wsfunction=core_enrol_get_enrolled_users&moodlewsrestformat=json&courseid=[idcourse]