feat: updates to SteamSample

This PR include various improvements that I made while developing Hellfront

[x] Use coherence Logger across all classes
[x] Move SteamServerInit call from SteamRelay into SteamManager
[x] Detect Steam graceful disconnect to suppress OOB errors
[x] SteamConnectionException to support proper error handling by the client / SteamManager
[x] SteamManager: Better exception handling
[x] Disable P2P and RS throttling

coherence / steam-integration-sample