Resolved findbugs issues in core and removed core from findbugs exclusions.
Resolved findbugs issues in cluster module
Restored real imports instead of *
Merge pull request #2068 from pveentjer/findbugs-core

Resolved findbugs issues in core and removed core from findbugs exclusio...
Merge pull request #2040 from pveentjer/findbugs-cluster

Resolved findbugs issues in cluster module
Resolved findbugs issues in cluster package