van Rijn's data (via Xiaonan Li).
Stations: total length of flume=30m, station 2 is at x=15m (i.e. middle point of trench), 
 station 1 is 3.5m upstream and station 3 is 3.5m downstream. See sta1* for format.

VanRijn_1987_data.DATA: shifted X to match my runs (i.e. center is x=15m).
