Add support for container registry operations (#278)

* Add initial container registry implementation

* Use variable error naming

* Fix godoc typo on object storage

* Add plans and regions list for Container Reg

* Add package comment

* Ignore dupl between VCR and Kubernetes

* Add the docker credential creation to container reg

Fix some linting and comment formatting as well

* Remove uneccesary comment

* Move container reg option type struct

* Add the metadata structs

* Add region datacenter struct

* Rename VCR update request param struct

* Fix kubernets test output

* Make registry repos struct private

* Rename VCR repository update data struct

* Make nested struct for plans its own type

* Add VCR tests

* Ignore goconst and dogsled in tests

.golangci.yaml

@@ -130,6 +130,8 @@ issues:
         - dupl
         - gosec
         - lll
+        - goconst
+        - dogsled
 
 run:
   timeout: 5m