Added hiera.yaml for key management.

hiera.yaml

+---
+version: 5
+
+defaults:  # Used for any hierarchy level that omits these keys.
+  datadir: data         # This path is relative to hiera.yaml's directory.
+  lookup_key: eyaml_lookup_key # eyaml backend
+  options:
+    pkcs7_private_key: /etc/puppetlabs/puppet/keys/private_key.pkcs7.pem
+    pkcs7_public_key:  /etc/puppetlabs/puppet/keys/public_key.pkcs7.pem
+
+hierarchy:
+  - name: "Environment"
+    path: "environment/%{::environment}.yaml"
+
+  - name: "OS family"
+    path: "os/%{facts.os.family}.yaml"
+
+  - name: 'common'
+    path: 'common.yaml'