Add support for auto registering EJB client intercpetors available in classpath, via service loader mechanism

Currently the EJB client API allows EJBClientContextInitializer(s) to be picked up from the classpath via service loader mechanism. These EJBClientContextInitializer(s) can then explicitly register any EJBClientInterceptor(s) to the EJBClientContext (being initialized).

It would be a lot easier if the EJB client API also allowed picking up and auto registering EJBClientInterceptor(s) via the service loader mechanism, so that the client application doesn't explicitly have to do so.