swamp: print node type before each log

[vgonkivs]

It's very hard to read logs without understanding which node the log belongs to.
We should print node type before each log("light:daser", "full:header/store")

[renaynay]

ipfs/go-log#140

[Wondertan]

We can do it with Knuu(#2240 ) if we manage to pipe the logs out of the nodes to the runner.