add functions to 8:
1. User Register            public static JSONArray userReg(JSONObject
info)
2. User Login                 public static JSONArray
userLogin(JSONObject info)
3. Add friend                 public static JSONArray
addFriend(JSONObject friendinfo)
4. Delete friend             public static JSONArray
deleteFriend(JSONObject friendinfo)
5. Get data                     public static JSONArray
getData(JSONObject info)
6. Write  Arrive data      public static JSONArray
writeArriveData(JSONObject data)
7. Write Leave data       public static JSONArray
writeLeaveData(JSONObject data)
8. Delete my data          public static JSONArray
deletemyData(JSONObject deleteid)