grouped by date

[
   {
      "created":"21.05.18 12:49",
      "content":[
         {
            "id":5,
            "title":"test title1 "
         },
         {
            "id":5,
            "title":"test title1 "
         }
      ]
   },
   {
      "created":"21.05.18 14:49",
      "content":[
         {
            "id":5,
            "title":"test title1 "
         },
         {
            "id":5,
            "title":"test title1 "
         }
      ]
   }
]