Use of TP.internal_pool can result in classloader leaks

As of JGroups 4.0, the ThreadFactory of the internal thread pool cannot be overridden. Consequently, there is no mechanism to associate newly spawned threads with a specific classloader. If an application thread results in the spawning of an thread in this internal pool [1], the application class loader can leak to other threads used the the JGroups channel.

[1] https://github.com/belaban/JGroups/blob/master/src/org/jgroups/protocols/TP.java#L1369