Query logic overhaul

[achingbrain]

Dist Paths

JS uses disjoint paths, go does not. We could ignore this for now and just lock to 1 (it might be interesting in the future to see how disjoint path performance behaves if we can get comparable performance with go on 1 path)

Evaluate Lookup/Query Logic

• This is where leveraging something like https://github.com/libp2p/py-libp2p-xor would be really valuable for finding bugs. The existing queries might be okay, but this will be the best way to diagnose bugs.
• We should also check query termination. Rough logic is stubbed out in https://hackmd.io/GUNOoRurR6igLoU984G5YQ with links to go dht lines for reference.

Problems:

• Key queries are really inconsistent right now. We should always be using sha256 hashes of the multihash but the APIs are currently inconsistent. This needs to get cleaned up. All APIs should just take multihashes.
  Verify go and js are generating the same hashes
• FindProviders should yield as they are found

[achingbrain]

Related: libp2p/js-libp2p#983

[vasco-santos]

it might be interesting in the future to see how disjoint path performance behaves

yes, I think this would be good. Both to compare with go and using something like testground

[achingbrain]

Hopefully @hacdias will be able to help us with Testground soon!