Update index.md

Added Grape::Resources to the list of related projects.

Author: Antonio Pagano

projects/index.md

@@ -16,6 +16,7 @@ comments: false
 * [grape-rabl](https://github.com/LTe/grape-rabl): Use Rabl templates.
 * [grape-active_model_serializers](https://github.com/jrhe/grape-active_model_serializers): User active_model_serializers.
 * [grape-msgpack](https://github.com/rosylilly/grape-msgpack): Message pack formatter.
+* [grape-resources](https://github.com/wawandco/grape-resources) Extension that allows to scaffold easily models that could not contain much logic.
 
 ### Caching