Update registry address

Author: rjeberhard

wercker.yml

@@ -47,7 +47,7 @@ build:
     no-cache: true
     registry-auth-config: |
       {
-        "https://index.docker.io/v1/": {
+        "https://registry-1.docker.io/v2/": {
           "username": "$REPO_USERNAME",
           "password": "$REPO_PASSWORD"
         }