INT-3185 Fix Direct Handlers When Exposed as MBean

When determining candidates for direct invocation, we need
to use the target of any existing proxy (such as JMX Metrics).

Copy ServiceActivatorDefaultFrameworkMethodTests to the JMX project
and adjust to work with JMX Proxies.

INT-3185: fix for AbstractSMHFBean#checkReuse

JIRA: https://jira.springsource.org/browse/INT-3185