Merge branch 'stable-3.8'

* stable-3.8:
  Fix pull-replication plugin startup which was always failing
  Add description for pending tasks metric
  Add description for in_flight metric
  Fixed typo in metric description

Change-Id: I9f749cbd7061a6c3c1adcfddf59e7b25229e0e1f
tree: 0588cada1cd07478ecee0b2c029aaa06e76e9ba8
  1. example-setup/
  2. src/
  3. .gitignore
  4. BUILD
  5. Jenkinsfile
  6. LICENSE