Adds performance tests for BlobStore-backed persistence
Use thread pool for Object Store persistence

- passes BrooklynProperties to BrooklynMementoPersisterToObjectStore
  so can read config like max thread pool size.
Incorporate comments for PR #41: thread pool for ObjectStore
This closes #41
Updated following further PR comments
Moves RecordingSshTool to core
Mark getting machine details as “inessential”
Logging in BrooklynFeatureEnablement.setDefault
JcloudsLocation: log port when waiting to ssh
Merge and close PR #52
Merge and close PR #43
Added apache-rat to main build (verify phase)
Added apache headers, where missing
Moved rat exclusions into subproject poms