anchor.diff:  ### Get Timetable for year and sem [GET]
   
   + Response 200 (application/json)
  +        
  +        {
  +            "last_synced": "2016-09-08T00:09:35+00:00",
  +            "data": [
  +                {
  +                    "module_code": "CS1010",
  +                    "lesson_type": "sectional",
  +                    "class_number": "1"
  +                }
  +            ]
  +        }
   
  -        [
  -            {
  -                "module_code": "CS1010",
  -                "lesson_type": "sectional",
  -                "class_number": "1"
  -            }
  -        ]
  +### Update modules in Timetable [POST]
   
  -### Add module to Timetable [POST]
  -
  -You can add a module to a timetable.
  +Timetable will be updated with all module data given in post request.
   The response is the complete timetable for year and sem with the module added.
   
   + Request (application/json)
  
positive.code:                 "module_code": "CS1010",
                  "lesson_type": "tutorial",
                  "class_number": "2",
              }
          ]
          
  
negative.code:                 "module_code": "CS1010",
                  "lesson_type": "tutorial",
                  "class_number": "2",
              },
              {
                  "module_code": "CS1010",
                  "lesson_type": "sectional",
                  "class_number": "1",
              },
              {
                  "module_code": "CS1231",
                  "lesson_type": "sectional",
                  "class_number": "1",
              }
          ]
  
  