Pydantic

* add `ConstrainedBytes` and `conbytes` types, [315](https://github.com/pydantic/pydantic/pull/315) Gr1N
* adding `MANIFEST.in` to include license in package `.tar.gz`, [358](https://github.com/pydantic/pydantic/pull/358) by samuelcolvin

* **breaking change**: don't call validators on keys of dictionaries, [254](https://github.com/pydantic/pydantic/pull/254) by samuelcolvin
* Fix validators with `always=True` when the default is `None` or the type is optional, also prevent
`whole` validators being called for sub-fields, fix [132](https://github.com/pydantic/pydantic/pull/132) by samuelcolvin
* improve documentation for settings priority and allow it to be easily changed, [343](https://github.com/pydantic/pydantic/pull/343) by samuelcolvin
* fix `ignore_extra=False` and `allow_population_by_alias=True`, fix [257](https://github.com/pydantic/pydantic/pull/257) by samuelcolvin
* **breaking change**: Set `BaseConfig` attributes `min_anystr_length` and `max_anystr_length` to
`None` by default, fix [349](https://github.com/pydantic/pydantic/pull/349) in [#350](https://github.com/pydantic/pydantic/pull/350) by tiangolo
* add support for postponed annotations, [348](https://github.com/pydantic/pydantic/pull/348) by samuelcolvin

* fix schema for `timedelta` as number, [325](https://github.com/pydantic/pydantic/pull/325) by tiangolo
* prevent validators being called repeatedly after inheritance, [327](https://github.com/pydantic/pydantic/pull/327) by samuelcolvin
* prevent duplicate validator check in ipython, fix [312](https://github.com/pydantic/pydantic/pull/312) by samuelcolvin
* add "Using Pydantic" section to docs, [323](https://github.com/pydantic/pydantic/pull/323) by tiangolo & [#326](https://github.com/pydantic/pydantic/pull/326) by samuelcolvin
* fix schema generation for fields annotated as `: dict`, `: list`,
`: tuple` and `: set`, [330](https://github.com/pydantic/pydantic/pull/330) & [#335](https://github.com/pydantic/pydantic/pull/335) by nkonin
* add support for constrained strings as dict keys in schema, [332](https://github.com/pydantic/pydantic/pull/332) by tiangolo
* support for passing Config class in dataclasses decorator, [276](https://github.com/pydantic/pydantic/pull/276) by jarekkar
(**breaking change**: this supersedes the `validate_assignment` argument with `config`)
* support for nested dataclasses, [334](https://github.com/pydantic/pydantic/pull/334) by samuelcolvin
* better errors when getting an `ImportError` with `PyObject`, [309](https://github.com/pydantic/pydantic/pull/309) by samuelcolvin
* rename `get_validators` to `__get_validators__`, deprecation warning on use of old name, [338](https://github.com/pydantic/pydantic/pull/338) by samuelcolvin
* support `ClassVar` by excluding such attributes from fields, [184](https://github.com/pydantic/pydantic/pull/184) by samuelcolvin

* fix `create_model` to correctly use the passed `__config__`, [320](https://github.com/pydantic/pydantic/pull/320) by hugoduncan

* **breaking change**: refactor schema generation to be compatible with JSON Schema and OpenAPI specs, [308](https://github.com/pydantic/pydantic/pull/308) by tiangolo
* add `schema` to `schema` module to generate top-level schemas from base models, [308](https://github.com/pydantic/pydantic/pull/308) by tiangolo
* add additional fields to `Schema` class to declare validation for `str` and numeric values, [311](https://github.com/pydantic/pydantic/pull/311) by tiangolo
* rename `_schema` to `schema` on fields, [318](https://github.com/pydantic/pydantic/pull/318) by samuelcolvin
* add `case_insensitive` option to `BaseSettings` `Config`, [277](https://github.com/pydantic/pydantic/pull/277) by jasonkuhrt

* move codebase to use black, [287](https://github.com/pydantic/pydantic/pull/287) by samuelcolvin
* fix alias use in settings, [286](https://github.com/pydantic/pydantic/pull/286) by jasonkuhrt and samuelcolvin
* fix datetime parsing in `parse_date`, [298](https://github.com/pydantic/pydantic/pull/298) by samuelcolvin
* allow dataclass inheritance, fix [293](https://github.com/pydantic/pydantic/pull/293) by samuelcolvin
* fix `PyObject = None`, fix [305](https://github.com/pydantic/pydantic/pull/305) by samuelcolvin
* allow `Pattern` type, fix [303](https://github.com/pydantic/pydantic/pull/303) by samuelcolvin