:bug: Avoid multiple GuiceLocator instances, and handle potential multiple KapuaMessageListeners

[dseurotech]

Should guicelocator fail at broker startup, multiple instances of (Kapua)MessageListener are istantiated, failing device login due to split request/response maps. In general, guice modules should avoid doing logic, and should avoid failing. Guice cannot guarantee that singleton objects previously instantiated are killed - which in some cases can be very distruptive. This pr both avoids multiple guiceLocator instantiation attempts within a single process, but also puts in place safeguards that ensure that message correlation will continue to work even if there are multiple (Kapua)MessageListener (possibly due to changes in the wiring).