Autogeneration of API, using genreateds_config.py to ensure correct naming conventions.

All that is needed is the Schema - as long as generateds_config.py and helper_methods are present, nml.py should be generated correctly.

Unit tests should be run to confirm this.

generateDS.py should be invoked in this folder (so that generateds_config.py can be located) with the following command (namespace def here will be mended when it's become stable)

   $ generateDS.py -o nml.py --silence --user-methods=helper_methods NeuroML_v2beta.xsd
