Don't output nonsense ownership without a keyspace

Patch by Steven Nelson, reviewed by brandonwilliams for CASSANDRA-7173
CASSANDRA-7507 - OOM killer cherry-picked
Reorder enum to be consistent with config file
Added doc for new options
Added 'die' logic to existing failure detection points
Added unit tests for JVMStabilityInspector
Added unit tests for new die logic (that was tested elsewhere)