* Add append_hash functionality to k8s module
append_hash adds a hash based on the contents of a ConfigMap
or Secret to the name - this enables immutable ConfigMaps and
Secrets.
* Provide k8s_config_resource_name plugin
The k8s_config_resource_name filter plugin provides a means of determining
the name of ConfigMaps and Secrets created with append_hash
* Add changelog fragment
* fix failing tests
* Update openshift version needed for append_hash
