* Link to project's DockerHub in README's section on nightly builds, add paragraph about nightly builds in installation docs
* Fix repositoryURL in sample seedJob configuration with SSH auth
* Slightly expand on #348
* Fix formatting in docs on Jenkins' customization, update plugin versions
* Add notes on Jenkins home Volume in Helm chart values.yaml and docs (#589)
* Don't validate external credential type
The operator shouldn't try to fetch credentials that have their types
defined as `external` - that means that credentials are supplied
externally, without using k8s secrets.
* Docs: Add example of `external` credential type