Queue cleanup

Remove stalled items waiting in Jenkins queue.Plugin allows administrator to configure queue wait timeout and item regex pattern. All items matching pattern and waiting longer than timeout hours will be removed from the queue.

Operation of the cleanup task is logged in org.jenkinsci.plugins.queuecleanup. Task checking period can be configured using org.jenkinsci.plugins.queuecleanup.QueueCleanup.period (default 1h).