Reintroduce a proper implementation for the Kademlia table

[ElFantasma]

For the sake of finding peers aggressively we replaced the Kademlia table implementation for a simpler HashMap based data structure.

• We should take a look to the previous implementation and re-implement required features (and check if there is some code there we can re-use)
• Also, evaluate if the Kademlia table is a good candidate to be implemented with a spawned GenServer.
• And let's be sure we are not using a bunch of Arc<Mutex<...>> for every field in the data structure... Worst case we should have a singe Arc<Mutex<...>> for the whole structure
• We should use xor distance instead of logarithmic distance