[NEXUS-6072] Refactor internal capability reference statuses & error handling

Signed-off-by: Alin Dreghiciu <adreghiciu@gmail.com>
[NEXUS-6070] Transition capability to removed regardless if onRemove() fails

Signed-off-by: Alin Dreghiciu <adreghiciu@gmail.com>
[NEXUS-6072] Replace AbstractLoggingComponent -> ComponentSupport

Signed-off-by: Alin Dreghiciu <adreghiciu@gmail.com>
[NEXUS-6072] Log stack trace only on debug level

Signed-off-by: Alin Dreghiciu <adreghiciu@gmail.com>
Configure capabilities loggers

Signed-off-by: Alin Dreghiciu <adreghiciu@gmail.com>
Update to goodies 1.8-SNAPSHOT for Loggers and ComponentSupport changes
Use ComponentSupport where possible.
Use static class ref for logger creation where possible.
Drop pointless getLogger() methods
Merge pull request #215 from sonatype/NEXUS-6072-failure-during-capab-load

REVIEW: [NEXUS-6072] Refactor internal capability reference statuses & error handling
Use ComponentSupport where possible.
Use static class ref for logger creation where possible.
Drop duplicate logger creating when super-class creates logger instance
Drop link to book until we figure out how to add this generally lets not show it
Merge pull request #217 from sonatype/logger-create-tidy

REVIEW: Logger create tidy
[NEXUS-6073] update to xstream 1.4.5, configure client to ingore unknown elements
[NEXUS-6063] update httpclient 4.2.6 and httpcore 4.2.5
Merge pull request #219 from sonatype/NEXUS-6063-update-httpclient

TRIVAL: [NEXUS-6063] update httpclient 4.2.6 and httpcore 4.2.5
Always show capability lifecycle error stack traces

Signed-off-by: Alin Dreghiciu <adreghiciu@gmail.com>
Drop logging of exception class/message as we now show stack traces

Signed-off-by: Alin Dreghiciu <adreghiciu@gmail.com>
Avoid a null message when capability is not configured

Signed-off-by: Alin Dreghiciu <adreghiciu@gmail.com>
Use exception vs exception message for capability state description in case of transition exceptions

Signed-off-by: Alin Dreghiciu <adreghiciu@gmail.com>
Merge pull request #218 from sonatype/NEXUS-6073-update-xstream

REIVEW [NEXUS-6073] update to xstream 1.4.5, configure client to ingore unknown elemnets
Merge remote-tracking branch 'origin/master' into NEXUS-6050-improve-ar-logging