ISPN-3950 Allow deployment of event filters and converters in server

https://issues.jboss.org/browse/ISPN-3950

A long awaited PR completing functionality in Hot Rod event (barring some small fixes) by allowing filter and converter instances to be deployed in Infinispan Servers. Adding filters and converters is a dynamic process now to make it easier to fit into the deployment model.

This PR also includes refactoring of filter and converter factory classes to `core` module, as agreed on a dev discussion.
Customise it by removing it :)