Add client authentication in ethbadgermpc / asynchromix2 example

[sbellem]

Relevant links:

• aiohttp server: https://docs.aiohttp.org/en/stable/web_reference.html#aiohttp.web.TCPSite
• aiohttp client: SSL control for TCP sockets
• OpenSSL Certificate Authority
• Python ssl module: https://docs.python.org/3/library/ssl.html
• Is it possible to create an X.509 certificate from an Ethereum/Bitcoin private key?

[sbellem]

Examples

• http://steven.casagrande.io/articles/python-requests-and-ssl/

aiohttp_security

Try using this aiohttp_security.