Improve generator documentation

Specification/BrAPI-Schema/README.md

@@ -0,0 +1,15 @@
+## JSON Specification 
+
+The BrAPI Specification defined as a JSON Schema. The schema is 
+defined in individual files per Entity in separate models.
+Some files contain more than one definition where the entity has
+Value Types that are used only by entity. 
+
+[BrAPI-Common](./BrAPI-Common) contains definitions that are used the
+accose the four main.
+
+[Requests](./Requests) defines the query model in the form of request 
+object definitions for the primary entity models. 
+Shared parameters and object definition between these definitions are placed in the
+[Parameters](./Requests/Parameters) and [Schemas](./Requests/Schemas) 
+directories respectively.

Specification/BrAPI-Schema/Requests/Parameters/README.md

@@ -0,0 +1,3 @@
+## Request parameters 
+
+This directory contains parameters shared between [Requests](../). 

Specification/BrAPI-Schema/Requests/Schemas/README.md

@@ -0,0 +1,3 @@
+## Request object definitions
+
+This directory contains object definitions shared between [Requests](../).