Sankey plots are a type of diagram that is convenient to
illustrate how flow of information, resources etc. separates and joins,
much like observing how rivers split and merge. For example, they can be
used to compare different clusterings.
0.6 -- (i) you can specify the position of the text label (using the
"pos" parameter of text()); (ii) graphics state is now restored
correctly; (iii) you can add the plots to existing graphics using the