Migrate to DH-managed config files

Use the Deckhand engine module directly to manage local configuration
files during CLI usage.

Note: not doing document validation as DH currently requires schemas to
be sourced from the database. Simple schema validation in place.

- Layering/substitution
- Schema validation based on DataSchema documents in payload
- Add deckhand to requirements

A few tooling updates

- concatenate test & schema yaml files into a single file to avoid name
  conflicts
- make nginx directory in build-scripts stage

Change-Id: I2d56244f01c58052f14331bc09fd5843d4c95292

examples/basic/KubernetesNetwork.yaml

@@ -6,6 +6,7 @@ metadata:
   layeringDefinition:
     abstract: false
     layer: site
+  storagePolicy: cleartext
 data:
   dns:
     cluster_domain: cluster.local