Support DHT-based Peer routing over HTTP

> part of https://github.com/ipfs-shipyard/someguy/issues/13

- [ ] Create IPIP that extends  API introduced in [IPIP-337](https://github.com/ipfs/specs/pull/337) to support [DHT peer records from libp2p spec ](https://github.com/libp2p/specs/tree/master/kad-dht#peer-routing)
  - [ ] wip: https://github.com/ipfs/specs/pull/417
- [ ] Implement support for it in `someguy` (backed by IPFS DHT)


