* Begin swap of requests-async for httpx
* Finalize httpx adoption and resolve tests
Resolve linting and formatting
* Remove documentation references to requests-async in favor of httpx
Update all tests to be compatible with requests-async
Cleanup testing client changes with black and isort
Remove Python 3.5 and other meta doc cleanup
rename pyproject and fix pep517 error
Add black config to tox.ini
Cleanup tests and remove aiohttp
tox.ini change for easier development commands
Remove aiohttp from changelog and requirements
Cleanup imports and Makefile
* This commit adds handlers for the asyncio/uvloop protocol callbacks for pause_writing and resume_writing.
These are needed for the correct functioning of built-in tcp flow-control provided by uvloop and asyncio.
This is somewhat of a breaking change, because the `write` function in user streaming callbacks now must be `await`ed.
This is necessary because it is possible now that the http protocol may be paused, and any calls to write may need to wait on an async event to be called to become unpaused.
Updated examples and tests to reflect this change.
This change does not apply to websocket connections. A change to websocket connections may be required to match this change.
* Fix a couple of PEP8 errors caused by previous rebase.
* update docs
add await syntax to response.write in response-streaming docs.
* remove commented out code from a test file
