Upgrade architecture + 5.0 Bot API (#469)
* Moved `methods`, `types` and `client` to root package
* Removed update handler from routers to dispatcher
* Reworked events propagation mechanism to handlers
* Reworked inner middlewares logic (very small change)
* Updated to Bot API 5.0
* Initial migration from MkDocs to Sphinx + config for readthedocs
* feat(proxy): proxy for aiohttp,base sessions
Add support for proxies in aiohttp session with aiohttp_socks library,
edit BaseSession class to support proxies for other sessions in future.
* fix(annotation): missing underscore before "private" typevar
* chore: remove redundant of proxy_url schema for socks version
* test: add missing test
Add missing test, remove BaseSession.cfg and switch to
implementing class' "private" traits, add aiohttp_socks in dependency list as
optional and extra.
* feat(session):
Implement asyncio session for requests [wip]
* feat(proxy chain): Chained proxy support in aiohttp session
Add ChainProxyConnector support, !pin pydantic to "1.4", add
documentation on aiohttp connector.
* style(mypy): apply linter changes
* tests(mock): remove await for magic mock
* fix dangling dependency
* refactor(generic):
get rid of generic behaviour for base session
