Adding information about imports in schemas to design.md

docs/design/design.md

@@ -127,6 +127,7 @@ more details, including:
 
 * info: more information about the template, including long description and
   title
+* imports: any sub-imports used by this template (may be relative path or URL)
 * required: properties which are required when instantiating the template
 * properties: JSON Schema descriptions of each property the template accepts
 
@@ -137,6 +138,9 @@ info:
   title: The Example
   description: A template being used as an example to illustrate concepts.
 
+imports:
+- path: helper.py
+
 required:
 - prop1