fixed problem with missing students in office admin list

sails/src/api/models/Supervisor.js

@@ -259,6 +259,7 @@ module.exports = {
       function (err) { // loop has end
         // Get all students from the office if user is administrator
         if (sup.office && sup.office.admin == sup.id) {
+	  var officeStudents;
 
           Student.find({ office: sup.office.id }).populate('lastInstruction')
           .then(function (officeStudents) {
@@ -268,14 +269,13 @@ module.exports = {
               student.current_instruction = student.lastInstruction[0] ? student.lastInstruction[0].ins_name : "no_instruction";
               return student;
             });
-            l.concat(officeStudents);
-            callback(null, lodash.uniq(l, false, 'id'));
+            l = l.concat(officeStudents);
+            callback(err, lodash.uniq(l, false, 'id'));
           })
           .catch(function (err) {
             callback(err, l);
           });
         }
-        callback(err, l);
       }); // end async.eachSeries
     })
     .catch((err) => {