code: public <T> T getItem(final List<T> items, final int probability) {
      return getItem(items, probability, null);
    }
docs: Returns a random item from a list of items or the null depending on the probability parameter. The probability
  determines the chance (in %) of returning an item off the list versus null.
  
  @param <T> Item type in the list and to return
  @param items List of items to choose from
  @param probability chance (in %, 100 being guaranteed) of returning an item from the list
  @return Item from the list or null if the probability test fails.