ISPN-4363 Add documentation for Cluster Listeners

* Added documentation about cluster listeners
* Added documentation about filters
* Added documentation about retry

https://issues.jboss.org/browse/ISPN-4363
you are repeating the sentence above and I think it isn't necessary. IMO, you should be direct:

The cluster listeners should be used when it is desirable to listen to the cache events on a single node. To do so (...)