Mostly switch over from old hackish system to io-streams and hydra-print
Debugging: it was the subprocess that was feeding EOS's.
First kind of working hydraprint version (works with 182551c3b06db).  Doesn't exit.
Switch to using hydraPrintStatic because we know the number of workers.
Add an example
Remove a lot of no longer needed code (Buffers, parfor twophase, etc).  Tweak how benchmark.hs finds ntimes_minmedmax