clarify map feature

Author: mr-c

v1.0/Workflow.yml

@@ -39,6 +39,29 @@ $graph:
       Since draft-3, this draft introduces the following changes and additions:
 
         * The 'inputs' and 'outputs' fields have been renamed 'in' and 'out'.
+        * Syntax simplifcations: denoted by the map<> syntax. Example: `in`
+          contains a list of items, each with an id. Now one can specify
+          a mapping of that identifier to the corresponding
+          `InputParameter`.
+          ```
+          in:
+           - id: one
+             type: string
+             doc: First input parameter
+           - id: two
+             type: int
+             doc: Second input parameter
+          ```
+          can be
+          ```
+          in:
+           one:
+            type: string
+            doc: First input parameter
+           two:
+            type: int
+            doc: Second input parameter
+          ```
 
       ## Purpose