Adds isDistributedLocked() for global semantics + some other tweaks

[john-morales]

• Adding isDistributedLocked() for global semantics; if lock not held by current process then queries DB for lock status.
• Can now maintain distinct service instances for different service options.
• Setting background monitoring threads as daemons so they cannot prevent JVM shutdown.
• Overriding finalize as safety measure to ensure lock's cleaned up even if lock not explicitly destroyed before leaving scope.

Thanks Deft Labs!