/// <summary>
 /// Construct the achievement database from the supplied JSON data
 /// </summary>
 /// <param name="json">JSON data</param>
 private void BuildDatabaseFromJSON(string json)
 {
     /*
      *  Take the string of JSON and convert it into a list of achievements
      *  achievementList is a list of Achievement, and our JSON file's
      *  top-level array contains an achievement in each element
      */
     achievements = JsonUtility.FromJson <AchievementCollection>(json);
     // Add each decoded achievement to the achievement database
     foreach (Achievement achievement in achievements.AchievementList)
     {
         Journal.Create(achievement);
     }
 }