Shutdown hook causes issues due to lack of dependency ordering

An issue was recently reported against https://github.com/mpilone/hazelcastmq where a `com.hazelcast.core.HazelcastInstanceNotActiveException` is raised during application shutdown. I tracked the issue down to the fact that Hazelcast registers a shutdown hook by default. This causes problems if the application depends on using a shutdown hook itself because the order of the hook execution by the JVM is not guaranteed which means Hazelcast could (and usually is) shutdown before the rest of the application.

I found a workaround of setting the property `config.setProperty(GroupProperties.PROP_SHUTDOWNHOOK_ENABLED, "false");` which disables the Hz shutdown hook.

It would be nice if this was a top level field on the Hz configuration or if Hz didn't register a shutdown hook by default and instead depended on the application to properly shut it down like most other server libraries. It seems like adding a shutdown hook should be an optional feature, not the default behavior. Maybe adding an `autoShutdown` option to the configuration with a default of false would make more sense.

The details of the issue reported to HzMq can be found here: https://github.com/mpilone/hazelcastmq/issues/4

Start by locating Hazelcast's configuration handling and the code that registers the JVM shutdown hook; compare the existing GroupProperties.PROP_SHUTDOWNHOOK_ENABLED workaround with the requested top-level configuration behavior. Review the linked HazelcastMQ issue for the failure context, then define and test one consistent opt-in or opt-out shutdown policy before implementation.

Written by the indexing model from the issue text.