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Improvements
- ``FHIRAbstractModel::json`` now takes additional parameter ``return_bytes``, indicates json string would be bytes. [nazrulworld]
- Issue38 Add support for FHIR comments. As per suggestion of comments in json from `Grahame Grieve <http://www.healthintersections.com.au/?p=2569>`_, now ``fhir_comments`` is accepted. [nazrulworld]
- FHIR comments filter option is added in ``FHIRAbstractModel::json``, means it is possible to exclude any comments while generating json string by providing parameter ``exclude_comments`` value. [nazrulworld]
- More FHIR DSTU2 resources have been added. [Itay Goren]