Made structural changes to server-side Preference code based on feedback

model/preference.go

@@ -32,15 +32,6 @@ func (o *Preference) ToJson() string {
 	}
 }
 
-func PreferenceListToJson(o []*Preference) string {
-	b, err := json.Marshal(o)
-	if err != nil {
-		return ""
-	} else {
-		return string(b)
-	}
-}
-
 func PreferenceFromJson(data io.Reader) *Preference {
 	decoder := json.NewDecoder(data)
 	var o Preference
@@ -52,17 +43,6 @@ func PreferenceFromJson(data io.Reader) *Preference {
 	}
 }
 
-func PreferenceListFromJson(data io.Reader) []*Preference {
-	decoder := json.NewDecoder(data)
-	var o []*Preference
-	err := decoder.Decode(&o)
-	if err == nil {
-		return o
-	} else {
-		return nil
-	}
-}
-
 func (o *Preference) IsValid() *AppError {
 	if len(o.UserId) != 26 {
 		return NewAppError("Preference.IsValid", "Invalid user id", "user_id="+o.UserId)