Implements enrolments management

By implementing `enrol_plugin::allow_manage()` an user with `enrol/apply:manage` capability can change an enrolment status, starttime and endtime.

db/access.php

@@ -49,6 +49,16 @@ $capabilities = array(
         )
     ),
 
+    /* Manage enrolments of users. */
+    'enrol/apply:manage' => array(
+        'captype' => 'write',
+        'contextlevel' => CONTEXT_COURSE,
+        'archetypes' => array(
+            'manager' => CAP_ALLOW,
+            'editingteacher' => CAP_ALLOW,
+        )
+    ),
+
     /* Unenrol a user */
     'enrol/apply:unenrol' => array(
         'captype' => 'write',

lang/en/enrol_apply.php

@@ -81,6 +81,7 @@ $string['status'] = 'Allow Course enrol confirmation';
 $string['confirmenrol'] = 'Manage application';
 
 $string['apply:config'] = 'Configure apply enrol instances';
+$string['apply:manage'] = 'Manage user enrolments';
 $string['apply:manageapplications'] = 'Manage apply enrolment';
 $string['apply:unenrol'] = 'Cancel users from the course';
 $string['apply:unenrolself'] = 'Cancel self from the course';

lib.php

@@ -59,6 +59,10 @@ class enrol_apply_plugin extends enrol_plugin {
         }
         return parent::allow_unenrol_user($instance, $ue);
     }
+    public function allow_manage(stdClass $instance) {
+        // Users with manage cap may tweak period and status.
+        return true;
+    }
     /**
      * Returns link to page which may be used to add new instance of enrolment plugin in course.
      * Multiple instances supported.
@@ -213,6 +217,10 @@ class enrol_apply_plugin extends enrol_plugin {
                 $url,
                 array('class' => 'unenrollink', 'rel' => $ue->id));
         }
+        if ($this->allow_manage($instance) && has_capability("enrol/apply:manage", $context)) {
+            $url = new moodle_url('/enrol/editenrolment.php', $params);
+            $actions[] = new user_enrolment_action(new pix_icon('t/edit', ''), get_string('edit'), $url, array('class'=>'editenrollink', 'rel'=>$ue->id));
+        }
         return $actions;
     }