[WIP] Feature/swagger model parser

[EmCousin]

This PR aims to answer #4

• It provides a custom model parser, allowing to generate response documentation based on a fast_jsonapi serializer.
  • The value example is generated as well
  • The generated values for the corresponding attributes are more relevant if the serializers are based from ActiveRecord models

Things to be done before merging

• Unit tests
• Maybe provide better documentation about dependencies
• Provide a changelog file
• ... ?

[EmCousin]

This PR will as well close #1