Reformat schema to be in a more displayable format.

def reformat_schema(model):
    """ Reformat schema to be in a more displayable format. """
    if not hasattr(model, 'schema'):
        return "Model '{}' does not have a schema".format(model)

    if 'properties' not in model.schema:
        return "Schema in unexpected format."

    ret = copy.deepcopy(model.schema['properties'])

    if 'type' in ret:
        del(ret['type'])

    for key in model.schema.get('required', []):
        if key in ret:
            ret[key]['required'] = True

    return ret