seperated todoist and habitica api calls into services

Habitica.Todoist.Integration.Model/Todoist/SyncResponse.cs

@@ -1,4 +1,5 @@
-using System;
+using Newtonsoft.Json;
+using System;
 using System.Collections.Generic;
 using System.Text;
 
@@ -6,8 +7,11 @@ namespace Habitica.Todoist.Integration.Model.Todoist
 {
     public class SyncResponse
     {
+        [JsonProperty("sync_token")]
         public string Sync_token { get; set; }
+        [JsonProperty("full_sync")]
         public bool Full_sync { get; set; }
+        [JsonProperty("itmes")]
         public List<Item> Items { get; set; }
     }
 }