Pydantic

* 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

* dataclasses decorator, [269](https://github.com/pydantic/pydantic/pull/269) by Gaunt and samuelcolvin

* fix issue where int_validator doesn't cast a `bool` to an `int` [264](https://github.com/pydantic/pydantic/pull/264) by nphyatt
* add deep copy support for `BaseModel.copy()` [249](https://github.com/pydantic/pydantic/pull/249), gangefors

* raise an exception if a field's name shadows an existing `BaseModel` attribute [242](https://github.com/pydantic/pydantic/pull/242)
* add `UrlStr` and `urlstr` types [236](https://github.com/pydantic/pydantic/pull/236)
* timedelta json encoding ISO8601 and total seconds, custom json encoders [247](https://github.com/pydantic/pydantic/pull/247), by cfkanesan and samuelcolvin
* allow `timedelta` objects as values for properties of type `timedelta` (matches `datetime` etc. behavior) [247](https://github.com/pydantic/pydantic/pull/247)