XCOMMONS-916: Refactor logging API to reuse new slf4j LoggingEvent APIs

.../org/xwiki/extension/cluster/internal/RemoteListener.java

.../xar/internal/handler/packager/DocumentMergeImporter.java

...tension/xar/internal/handler/XarExtensionHandlerTest.java

...al/handler/packager/DefaultDocumentMergeImporterTest.java

...rg/xwiki/extension/xar/internal/job/RepairXarJobTest.java

...i/extension/script/ExtensionManagerScriptServiceTest.java

...n/java/org/xwiki/logging/script/LoggingScriptService.java

...ervation/remote/internal/converter/LogEventConverter.java

...rvation-remote/src/main/resources/META-INF/components.txt

...rc/test/java/org/xwiki/observation/remote/TCPROMTest.java

...core/src/main/java/com/xpn/xwiki/doc/XWikiAttachment.java

...ldcore/src/main/java/com/xpn/xwiki/doc/XWikiDocument.java

...re/src/main/java/com/xpn/xwiki/doc/merge/MergeResult.java

...rc/main/java/com/xpn/xwiki/internal/merge/MergeUtils.java

...e/src/main/java/com/xpn/xwiki/objects/BaseCollection.java

...dcore/src/main/java/com/xpn/xwiki/objects/BaseObject.java

...ore/src/main/java/com/xpn/xwiki/objects/BaseProperty.java

...oldcore/src/main/java/com/xpn/xwiki/web/ImportAction.java

...c/test/java/com/xpn/xwiki/doc/XWikiDocumentMergeTest.java

...est/java/com/xpn/xwiki/internal/merge/MergeUtilsTest.java