ISPN-4753 Add oldValue, oldMetadata and retry flag to filter and converter for
Cluster Listeners.

* Added new filter and converter specifically for listeners
Fix the sample correctness test to look for the files in their new home
ISPN-4631 Add explicit check that cluster was formed

* Added check that cluster has 2 members
* Adjust initial number of nodes to avoid delays
* Renamed jgroups config files to "tcp" as transport was switched to TCP
ISPN-4756 Upgrade to protobuf-2.6.0 and protostream-2.0.0.Alpha3
ISPN-4357 Use a specific cache for managing protofiles