code: public final Ix<List<T>> bufferSplit(IxPredicate<? super T> predicate) {
          return new IxBufferSplit<T>(this, nullCheck(predicate, "predicate is null"));
      }
docs: Buffer until an item is encountered for which the predicate returns true,
  triggering a new buffer.
  <p>Neither the previous nor the next buffer will contain the item that caused the
  split
  @param predicate the predicate called with each item and should return false
  to trigger a new buffer
  @return the new Ix instance
  @see #bufferUntil(IxPredicate)
  @see #bufferWhile(IxPredicate)
  @since 1.0