MDL-29030 migrate and cleanup log report

AMOS BEGIN
 MOV [log:view,coursereport_log],[log:view,report_log]
 MOV [log:viewtoday,coursereport_log],[log:viewtoday,report_log]
AMOS END

course/lib.php

@@ -831,13 +831,19 @@ function print_log_ods($course, $user, $date, $order='l.time DESC', $modname,
 
 function print_log_graph($course, $userid=0, $type="course.png", $date=0) {
     global $CFG, $USER;
+
+    // note: this is a hack - we should not use plugins from core
+    if (!file_exists($CFG->dirroot.'/report/log/graph.php')) {
+        return;
+    }
+
     if (empty($CFG->gdversion)) {
         echo "(".get_string("gdneed").")";
     } else {
         // MDL-10818, do not display broken graph when user has no permission to view graph
-        if (has_capability('coursereport/log:view', get_context_instance(CONTEXT_COURSE, $course->id)) ||
+        if (has_capability('report/log:view', get_context_instance(CONTEXT_COURSE, $course->id)) ||
             ($course->showreports and $USER->id == $userid)) {
-            echo '<img src="'.$CFG->wwwroot.'/course/report/log/graph.php?id='.$course->id.
+            echo '<img src="'.$CFG->wwwroot.'/report/log/graph.php?id='.$course->id.
                  '&amp;user='.$userid.'&amp;type='.$type.'&amp;date='.$date.'" alt="" />';
         }
     }