Can't set multiple cookies

[adamchainz]

I just finished upgrading my similar package apig-wsgi to support v2. I used this library as reference. On the way I spotted a bug - the set-cookie header in responses does work, but if a response sets more than one cookie, you can only have one header, so the other cookies will get dropped. You need to pull the cookie headers out into the cookies return array.

Additionally ths library isn't returning the full response object (doc'd at bottom of this page), I'm not sure if there are potential issues there e.g. api gateway may try and infer if response content is base64 encoded (not documented ofc).