Memory leak when adding/removing a lot of routes with JMX enabled

If you add and remove a lot of routes to CamelContext and have JMX enabled, then the DefaultManagementLifecycleStrategy will accumulate a map of provisional JMX performance counters for the route mbeans. The map should be cleared after usage, as the map is no longer needed.

Memory will accumulate as the map has reference to old objects which cannot be GC.