Remove ROADMAP file
Remove ROADMAP file

The only ROADMAP now is small fixes toward making it stable
and very little interface changes, so the file is not that
useful anymore.

turtleDeng/cowboy,K2InformaticsGmbH/cowboy,hairyhum/cowboy,ninenines/cowboy,rabbitmq/cowboy,bsmr-erlang/cowboy,kivra/cowboy,CrankWheel/cowboy