Decomposed elements of emitter.

src/emitter.hs: web controller and view elements removed, terminal view inserted
src/flow.hs: random walk computation removed and simple summation of stream (inc) inserted.
added notes, serialising scan and changed to Edge.sh
switched flow.hs to Output director pattern
added save/load/replay testing in event.hs
Attempt at introducing a binary save (rather than a bytestring one).  writeFile was ok but readFile is more difficult due to Data.Binary requiring lazy bytestrings, when Pipes.ByteString uses strict ones.
timestamp version in event-time.sh
major refactor, separating event, edge and mvc wiring concepts
added dot graph
Capitalize emitter.hs so it works as a module