ISPN-3402 Add JDBC Cache Store config to RHQ plugin

* Added JDBC types to rhq
* Had to add fix for map within map for rhq agent code
ISPN-4664 Pass isCommandRetried flag in remote client events.

* Events being the result of retried commands can be useful for
clients to decide what to do with the event.
* Updated Hot Rod 2.0 protocol to add isCommandRetried flag.
* Updated user documentation on the events received by clients.