Merge pull request #412 from wercker/registry-v2-docs

Registry v2 docs

content/docs/containers/pushing-containers.md

@@ -55,6 +55,8 @@ field contains the repository that you want to push to (in this case the
 username `turing` with the `bar` image), and `registry` is
 the URL of your Docker registry.
 
+>NOTE: if you want to push to a registry that supports V2 of the API, simply append "/v2" to your registry URL.
+
 If your container needs a `cmd` to be run on start up of the container along
 with a `port` that your application listens on, you can "bake" that into
 the container as well:

content/docs/steps/internal-steps.md

@@ -63,7 +63,7 @@ The `internal/docker-push` step supports the following properties:
 - `message`: Set a comment on the layer.
 - `registry`: The endpoint of the registry. Leave empty for pushes to the
   Docker hub. For pushes to other registries, it should start with `https://`
-  and should be the same as the prefix of the `repository`.
+  and should be the same as the prefix of the `repository`. Append `/v2` to the URL to push to registries that support V2 of the registry API.
 - `user`: String value specifying the user inside the container.
 - `env` - A list of environment variables in the form of `["VAR=value"[,"VAR2=value2"]]`. Can be delimited by spaces or commas.
 - `labels` - Adds a map of labels to a container. To specify a map, pass your labels into the `wercker.yml` file in this format `["LABEL=label"[,"LABEL2=label2"]]`. Can be delimited by spaces or commas.