code: public Stream<T> separate(final T value) {
          return filter(new Func1<T, Boolean>() {
              @Override
              public Boolean call(T it) {
                  return ((it == null) ? (value != null) : !it.equals(value));
              }
          });
      }
docs: Returns a new stream that contains all items of the current stream except of a given item.
  
  @param value a value to filter out.
  @return a new stream that contains all items of the current stream except of a given item.