Add support for CGI middleware

[aymanbagabas]

Support using Giftless as a CGI module the same way Giftless supports WSGI.

[vit-zikmund]

This looks like a matter of uWSGI configuration than anything else. Giftless is actually served via uWSGI, which provides the WSGI interface. Feel free to contribute a working example.

[rufuspollock]

FIXED. From @vit-zikmund response my understand is that this is already possible and just requires a config in uWSGI config so i'm going to close.

@aymanbagabas hope this helped you.

@athornton @vit-zikmund lmk if any alternative views on this and can re-open.