NEXUS-6050: Improve logging
Merge remote-tracking branch 'origin/master' into NEXUS-6050-improve-ar-logging
NEXUS-6050: More logging improvements

Using goodies ComponentSupport instead of the deprecated
AbstractLoggingComponent
NEXUS-6050: Expose proxy repo for subclasses
NEXUS-6050: Expose maven proxy and use it in logging
NEXUS-6050: Fixing NPE prone logging
NEXUS-6050: Enhancing S3 scraper related log
NEXUS-6050: Cleanup
Merge pull request #221 from sonatype/NEXUS-6050-improve-ar-logging

NEXUS-6050: Improve logging in AR