JIRA: https://jira.spring.io/browse/INT-4361
* To get a gain of the method chain code flow and avoid extra annotation
parsing, add `.role(String)` hook to the `EndpointSpec`
* Delegate the provided `role` property to the `AbstractEndpoint`
* Register `AbstractEndpoint` as itself `SmartLifecycle` in the
`SmartLifecycleRoleController`
* Add `destroy()` to the `AbstractEndpoint` and remove it from the
`SmartLifecycleRoleController`
* Provide some Java 8 code style refactoring
* Rework XML parsers and Annotation processors to populate `role`
property on the `AbstractEndpoint`
* Wrap `roleController` bean extraction to the `NoSuchBeanDefinitionException` catch
* Fix several `AbstractEndpoint` implementation to properly call
`super.onInit()` which has been missed before
f7e75223c7