Connexion

* Objects and Arrays recursively construct examples (1148)
* Added `server_args` parameter to AbstractApp (1173)
* AIOHTTP: get rid of `asyncio.coroutine` (deprecated in Python 3.8) (1186)
* AIOHTTP: fix `_framework_to_connexion_response` for StreamResponse (1217)

* Fix variable scoping (1110)
* Fix aiohttp access_log duplicated if passed as argument (1113)
* Fix pythonic params (1116)
* Fix extra formData (1020)
* Fix nested additionalProperties (1138)
* Allow empty security definition

* Require Python 3.6 for pip installation (1108)

* Drop Python 2.7 support, support Python 3.8
* Convert responses to raise `ProblemException` (955)
* Add error path to schema validation
* Do not sanitize body keys in OpenAPI 3 (1008)
* Date/time serialization (851)
* Forward options to AioHTTP app (885)
* Returning tuples supported in AioHTTP (849)
* Allow Swagger UI configuration options (948)
* Remove security parameter to pass query validation (470)
* Allow users to enable debug mode via environment variable

* Handle deepObject and explode: true (971)
* Support jsonschema > 3.0.0 (1050)
* Drop Python 3.4 and 3.5. Add Python 3.8 (1056)
* Fix deprecated import (1044)
* Bump Flask version (995)

- AioHttpApi oauth middleware catches all OAuth problems (830)
- Serve YAML spec (842)
- Added MethodViewResolver (847)
- Fix swagger console backslash redirect for aiohttp (843)
- Fix uwsgi metric collection (972)
- Respond with problems by default in aiohttp (952)