[request] non-conservative flows, OR nodes by percentage.

[alexchandel]

At the moment, AFraction [2000] BFraction takes 2000 from AFraction and sends it to BFraction.

However, there are some cases where the flow is desired to change size between the beginning and end. The most obvious is when nodes are desired as percentages. In that case, the "total" in each layer may vary, due to reproduction/destruction between layers.

Please add an option for explicitly different bounds, like AFraction [2000, 1800] BFraction, or a "ratio" option, like AFraction [2000]/2 BFraction, or add the option to size all nodes as percentages.