Remove printf when specifying checksum

Get rid of the printf

Signed-off-by: Christoph Paasch <christoph.paasch@uclouvain.be>
Remove the window-tests from ack/data packets

It makes the tests quite unstable as the window depends on too many factors.
Separate tests should be done to verify the window.

Signed-off-by: Christoph Paasch <christoph.paasch@uclouvain.be>
More window-removals as they make tests unstable

Signed-off-by: Christoph Paasch <christoph.paasch@uclouvain.be>
Merge pull request #14 from cpaasch/master

Remove printf when specifying checksum