Update grape-ams link on index page (#34)

Update grape-active_model_serializers link on the index page

Author: jrhe

projects/index.md

@@ -15,7 +15,7 @@ comments: false
 * [grape-entity](https://github.com/ruby-grape/grape-entity): An API focused facade that sits on top of an object model.
 * [grape-rabl](https://github.com/ruby-grape/grape-rabl): Use Rabl templates.
 * [grape-roar](https://github.com/ruby-grape/grape-roar): Use Roar with Grape.
-* [grape-active_model_serializers](https://github.com/jrhe/grape-active_model_serializers): User active_model_serializers.
+* [grape-active_model_serializers](https://github.com/ruby-grape/grape-active_model_serializers): Use 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.