Expose configuration via JMX

This change exposes the SessionFlushValve and RedisStore configuration
via JMX.  The SessionFlushValve can be found at 'Catalina:type=Valve,c
ontext=<PATH>,host=<HOST>,name=SessionFlushValve' and has no exposed
attributes.  The RedisStore can be found at
'Catalina:type=Store,context=<PATH>,host=<HOST>,name=RedisStore' and
has the following attibutes:

* connectionPoolSize
* database
* host
* password
* port
* timeout
* uri

[#64605194]
Merge 64605194-configuration-via-jmx to master

[Completes #64605194]