* Rename NullAdapter to SimpleAdapter
* Introduce abstract Adapter class
* Organaze test structure to match convemtions
Add NullAdapater
* Configure adapter using ActiveModel::Serializer.config.adapter
* Get adapter instance using ActiveModel::Serializer::Adapter.adapter_for(serializer)
Serializer should be available wiithing adapter to inspect attributes and assotions
Test for SimpleAdapter#serializable_hash
Test for NullAdapter#serializable_hash
Concrete adapter should provide serializable hash for Adapter#to_json method
Move Adapter.adapter_for to Serializer.adapter
Add Serializer#associations
Wrap association into Serializers
start implementing json_api adapter to understand how associations should work
fix spelling
First try to implement ArraySerializer
Remove 1.9.3 from CI build as we dropped support
Include Enumerable to ArraySerializer
* Do not ingerit array serializer from Serializer
* Tests for ArraySerializer
rename simple adapter to json
JsonApi adapter: serialize association
Remove 'Adapter' suffix from adapters since they are in Adapter:: namespace
Merge remote-tracking branch 'upstream/master' into feature/adapter