This commit adds support to allow the LANCommander server to scale horizontally. Multiple instances of the application can be deployed for load-balancing purposes. This will require a load balancer in front of the instances, as well as either MySQL or PostgreSQL and a Redis cache.
Sends a keepalive/heartbeat signal across RPC while a game is running. Server-side this enables the ability to manage play session state with realtime information instead of hoping that the client will stop the play session. Keepalives are tracked in server cache allowing for future potential horizontally-scaled server instances.