The new -limit option makes the filter operate on top N nodes by score.
This also adds ENR attribute stats in the nodeset info command.
Node set commands are now documented in README.
This PR replaces the old test genesis.json and chain.rlp files in the testdata
directory for the eth protocol test suite, and also adds documentation for
running the eth test suite locally.
It also improves the test output text and adds more timeouts.
Co-authored-by: Felix Lange <fjl@twurst.com>
