Explicitly document streams API #1106
Description
http://aiohttp.readthedocs.io/en/stable/api.html looks like a piece of garbage.
Especially when I look on streaming API
http://aiohttp.readthedocs.io/en/stable/api.html#module-aiohttp.streams
It mixes native private methods like feed_eof() and feed_data() with decided to be used by top-level programmer like .read_any etc.
Moreover it doesn't suggest to use async for for iterating over incoming data and so on.
The doc should get rid of autodoc usage and switch to explicit documentation writing (as Python itself does).
The far blue sky goal is getting rid of autodoc usage at all for the project.