improved description of RTreeParams (ticket #1656; thanks to Nghia Ho)
improved description of RTreeParams (ticket #1656; thanks to Nghia Ho)

opencv/opencv,opencv/opencv,opencv/opencv,apavlenko/opencv,apavlenko/opencv,opencv/opencv,opencv/opencv,opencv/opencv,opencv/opencv,apavlenko/opencv,apavlenko/opencv,opencv/opencv,apavlenko/opencv,opencv/opencv,apavlenko/opencv,opencv/opencv