Checkpoint commit for OPENDJ-1288 :
Migrate I18n and logging support to i18n framework and SLF4J
Update and clean error and debug logging to align with review
comments : CR-2867
* Refactor DebugTargetConfiguration
** remove debug-level (ds-cfg-debug-level)
** remove debug-category (ds-cfg-debug-category)
** add enabled (ds-cfg-enabled)
** add debug-exceptions-only (ds-cfg-debug-exceptions-only)
* Refactor DebugLogPublisherConfiguration
** remove default-debug-level (ds-cfg-default-debug-level)
** remove default-debug-category (ds-cfg-default-debug-category)
** add default-debug-exceptions-only (ds-cfg-default-debug-exceptions-only)
* Update config.ldif and schema/02-config.ldif according to
configuration changes
* Remove LogLevel and LogCategory classes
* Uncomment dependency on opendj-slf4j-adapter and
re-enable disabled unit tests