Changes
* `Rule`'s does not return a list of errors. `Rule` returns a valid value if not raised `RuleError`(or `ListRuleError`). You can find all collected errors using `InvalidRequestError`. See `demo_error_formatter`. Attention! `demo_error_formatter` is just a demo(not supported). Feel free to suggest a new formatter.
* [error modifications](https://github.com/d-ganchar/flask_request_validator/commit/a0c7718d157d7a749e3f0d046ca636ab3be3ecc9)
* Added [DatetimeRule](https://github.com/d-ganchar/flask_request_validator/issues/59)
* `kwargs` is no longer supported in `routes`(see `ValidRequest` example below)
* Added [nested JSON validation](https://github.com/d-ganchar/flask_request_validator/wiki/Examples#jsonparam---nested-json-validation)