Allow $request_uri in REDIRECT_LOCATION

[Luke Cyca]

Often when redirecting between www and non-www, and between http and https, the path is included. For example using this nginx config:

return 301 https://www.vhost.domain.tld$request_uri;

I don't think that's possible with this docker image. It would be great if it was.

[Maxim Kosterin]

I am agree

[Adam K Dean]

Apologies @lukecyca @MaximStone, I didn't see this issue. This has now been resolved in #3 (thanks @dweevedi)