* feat: provide image with nginx
* Re-use parent container configuration and startup scripts
* Rewrite proxy Dockerfile:
* ARCH used to be hard-coded; is now set according to the architecture being built
* Build from the associated LedgerSMB base image (not from 'lsmb-split')
* More deletion of non-required files (/usr/share/doc/*)
* Fewer layers by combining RUN commands
* Use 'server-start' script generated by the installer instead of repeating ourselves
* Don't expose the status module
It won't be accessible anyway: the localhost address is the one inside the container...
* Ensure relative redirects
When the container port :80 is exposed as :8080 on the host,
nginx redirects to http://localhost:80/login.pl with a relative
path, instead of http://localhost:8080/login.pl; the container
isn't bound to :80, so that request fails...
* Rename proxy layer image
* Adjust 'build' script to publish base and regular images
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Co-authored-by: Walid Mujahid <walidmujahid@gmail.com>