Old 1.0.1 version is still supported as well. Cabal autodetects
which version is available, but in the Makefile, WITH_OLD_YESOD
has to be configured appropriately.
I have not squashed all the $newline warnings with the new Yesod.
They should go away eventually anyway as Yesod moves past that transition.
This avoids forking another process, avoids polling, fixes a race,
and avoids a rare forkProcess thread hang that I saw once time
when starting the webapp.
