Review JGroups protocol stack configs

For each AS release, AS asks the JGroups team to review the JGroups protocol stack configs the AS ships for correctness/confornance with latest best practices.

Per JBAS-7251, AS 5.2 will use a new JGroups minor version, 2.8, so for sure we want to do this review.

It's premature to do this review now; I still need to look at Branch_5_x and make sure various stuff that's been discussed recently is updated there. Early October is more appropriate.