A GenServer that periodically removes extra nodes from mnesia schema.

When a new node is started it automatically starts to sync both mnesia schema and data with other participating nodes. On the other hand when a node is terminated it's not automatically removed from mnesia schema (because mnesia has no idea whether the node will re-join the cluster or not).

This GenServer periodically cleans up any already-terminated nodes from mnesia schema by using hosts information from the underlying infrastructure. Without this cleanup the "already terminated nodes" would accumulate in mnesia schema and make startup of new nodes really slow (new node tries to sync with nonexisting nodes until timeout).

Depends on AntikytheraCore.ClusterHostsPoller.