An optimized version of splittingFlowOn that splits on
A flow that takes akka.util.ByteString, and turns it into UTF-8 strings, split on one of several split characters.
A flow that turns a stream of akka.util.ByteString into a stream of UTF-8 strings, each containing one line.
(Since version 2.2.3) Use splittingFlow instead
(Since version 2.5.0) Use alsoTo or alsoToMat instead