[feat] Redirect / to docs page

[choinek]

@ngpollock the reason for the "not found" errors is that you're trying to access localhost:8000/, but currently, there's nothing running on that endpoint (/.

You should use the endpoints provided in the documentation, like /ocr/request

https://github.com/CatchTheTornado/text-extract-api

@pkarw this leads me to consider that it might be worth route / to docs page, or if its not easy in FastAPI then do redirect from / to docs ;)

Originally posted by @choinek in #78 (comment)