Get an enumeration of known logger names.
Note: Loggers may be added dynamically as new classes are loaded.
This method only reports on the loggers that are currently registered.
It is also important to note that this method only returns the name
of a Logger, not a strong reference to the Logger itself.
The returned String does nothing to prevent the Logger from being
garbage collected. In particular, if the returned name is passed
to LogManager.getLogger(), then the caller must check the
return value from LogManager.getLogger() for null to properly
handle the case where the Logger has been garbage collected in the
time since its name was returned by this method.
Diagram: Logger