* addPeer() and addPeerNoWait() now returns PeerStatus, not bool.
Minor refactoring of PeerPool.
Fix tests.
* Refactor PeerPool.
Add lenSpace.
Add tests for lenSpace.
PeerPool.add procedures now return different error codes.
Fix SyncManager break/continue problem.
Fix connectWorker break/continue problem.
Refactor connectWorker and discoveryLoop.
Fix incoming/outgoing blocking problem.
* Refactor discovery loop.
Add checkPeer.
* Fix logic and compilation bugs.
* Adjust position of debugging log.
* Fix issue with maximum peers in PeerPool.
Optimize node record decoding.
* fix discoveryLoop.
* Remove aliases and fix tests using aliases.
* Refactor peer_pool.
Fix eth2_network peer counters.
Fix PeerPool do not allow to add more peers when empty space available.
* Remove unused imports.
* Add test for a bug.
* Fix eth2_network disconnect should deletePeer not release.
More PeerPool refactoring.
* Add "drop by score" ability to PeerPool.
Add tests.
Fix syncmanager queue to start from most fresh data.
* Fix endless cycle at the end of syncing process.