fastapi 0.12.0

on Python PyPI

Add additional responses parameter to path operation decorators to extend responses in OpenAPI (and API docs).

• It also allows extending existing responses generated from response_model, declare other media types (like images), etc.
• The new documentation is here: Additional Responses.
• responses can also be added to .include_router(), the updated docs are here: Bigger Applications.
• PR #97 originally initiated by @barsi.

Update scripts/test-cov-html.sh to allow passing extra parameters like -vv, for development.