'head' route on '/' does not need to return anything.
It's only a dummy route in order to get Spark to ignite.
This route can be removed if at least 1 other route exists.

Signed-off-by: Christian MICHON <christian.michon@gmail.com>
clean up: old code using real external static files

Signed-off-by: Christian MICHON <christian.michon@gmail.com>