This fixes issues with the protocol handshake and status exchange
and adds support for responding to GetBlockHeaders requests.
# Conflicts:
# cmd/devp2p/internal/ethtest/suite.go
# cmd/devp2p/internal/ethtest/types.go
This change adds a test framework for the "eth" protocol and some basic
tests. The tests can be run using the './devp2p rlpx eth-test' command.
# Conflicts:
# core/forkid/forkid.go
# eth/discovery.go
# eth/handler.go
# eth/helper_test.go
# eth/protocol_test.go
