The few hpack development tools are now integrated into the main
makefile, which allows to remove the original one which was causing
lots of build warnings. A README was added to explain how to build
instead.
The following directories were moved from contrib/ to dev/ to make their
use case a bit clearer. In short, only developers are expected to ever
go there. The makefile was updated to build and clean from these ones.
base64/ flags/ hpack/ plug_qdisc/ poll/ tcploop/ trace/