Method removeFromFlowSplit

Remove the given FlowBlock from the flow of the graph. It must have 2 inputs, and 2 outputs. The edges will be remapped so that - In(0) -> Out(0) and - In(1) -> Out(1) Or if \b flipflow is true: - In(0) -> Out(1) - In(1) -> Out(0) \param bl is the given FlowBlock \param flipflow indicates how the edges are remapped