code: public void getAllTraitID(Callback<List<Integer>> callback) throws NullPointerException {
  		gw2API.getAllTraitIDs().enqueue(callback);
  	}
docs: For more info on traits API go <a href="https://wiki.guildwars2.com/wiki/API:2/traits">here</a><br/>
  Give user the access to {@link Callback#onResponse(Call, Response)} and {@link Callback#onFailure(Call, Throwable)} methods for custom interactions
  
  @param callback callback that is going to be used for {@link Call#enqueue(Callback)}
  @throws NullPointerException if given {@link Callback} is empty
  @see Trait trait info