Discv5

[flcl42]

Resolves #4721

Adds discovery v5 in the following manner:

• discv5 enabled means discv4 disabled
• queries for all nodes on distance to self and to 3 random nodeIDs with interval of 30 seconds
• does not hold cache of discovered nodes, so duplicates handling is on peer pool
• saves all peer pool active nodes on shutdown to use them for discovery after restart

alias thing

There is an outdated dependency:

PierTwo.Lantern.Discv5.WireProtocol -> PierTwo.Lantern.Discv5.Enr -> Multiformats.Hash -> Portable.BouncyCastle **1.8.5**

We plan before the next release to update Multiformats.Hash with newer version of Portable.BouncyCastle, and use updated version in PierTwo.Lantern.Discv5

Types of changes

What types of changes does your code introduce?

• [ ] Bugfix (a non-breaking change that fixes an issue)
• [x] New feature (a non-breaking change that adds functionality)
• [ ] Breaking change (a change that causes existing functionality not to work as expected)
• [ ] Optimization
• [ ] Refactoring
• [ ] Documentation update
• [ ] Build-related changes
• [ ] Other: Description

Testing

Requires testing

• [ ] Yes
• [x] No

If yes, did you write tests?

• [ ] Yes
• [x] No

Notes on testing

OP/Base networks covered, others that have discv5 support need bootstrap peers to be added to the specs

Documentation

Requires documentation update

• [ ] Yes
• [x] No

Not yet

Requires explanation in Release Notes

• [x] Yes
• [ ] No

[flcl42]

@rubo the package has been published to the production feed; docker changes have been rolled back