[Epic] Better documentation

[shin-]

• Making use of Sphinx autodoc for API docs #454 Making use of Sphinx autodoc for API docs
• Document possible exceptions #499 Document possible exceptions
• Clean up documentation #821 Clean up documentation
• how to use the 'log-drive' #964 Hostconfig doc should provide the available list of ulimit names #943 Documentation for ulimits and logging configuration is absent / lacking
• Support ipv4_address and ipv6_address in create_endpoint_config #1083 (comment) Network documentation / thematic separation for API docs.

Main takeaways:

• API docs are poorly formatted and difficult to navigate.
• Some users find it valuable to have the documentation closer to the code itself.
• More information could be given about the behavior of our methods (exceptions raised, etc.)
• User guides in addition to functional documentation could prove useful.

[dnephin]

If I could add one more point, I think it would be awesome to have a link from the docker-py docs to the official API for the endpoint as well.

[shin-]

I didn't think of that, but you're right. Noting this down!