Remove folder-based versioning from manifests

This adapts manifests to be in line of using git reference
for refering to global/secrets repos instead of versioned folders.

Change-Id: I0100fb90666e335bd99d304b3804c180b25a9d16
Depends-On: https://review.openstack.org/#/c/577886/

global/schemas/pegleg/SiteDefinition/v1.yaml

@@ -5,15 +5,25 @@ metadata:
   name: pegleg/SiteDefinition/v1
 data:
   $schema: http://json-schema.org/schema#
-  type: object
 
+  type: object
   properties:
-    revision:
-      type: string
-      pattern: '^v.+$'
+    repositories:
+      type: object
+      additionalProperties:
+        type: object
+        properties:
+          revision:
+            type: string
+          url:
+            type: string
+        required:
+          - revision
+          - url
+
     site_type:
       type: string
   required:
-    - revision
     - site_type
   additionalProperties: false
+...