On leaving a cluster, generate a leave presence about all non-node-local MUC participants for all node-local MUC participants

Description

Left with a largely operational solo instance of Openfire, having just left the cluster, generate a leave presence for all MUC participants no longer reachable using the list created in https://igniterealtime.atlassian.net/browse/OF-2224

Environment

None

Assignee

Guus der Kinderen

Reporter

Dan Caseley