No config written for _SKIP_SELF_URL_PATH_CHECKS

[mitchins]

For convenience, it would be nice if a docker environment variable for _SKIP_SELF_URL_PATH_CHECKS could be read and written to config.php automatically. Many people use a reverse proxy with SSL termination in the web server, and so TTRSS will complain (even with forward-x-proto)

putenv('_SKIP_SELF_URL_PATH_CHECKS=true');

I can raise a pull request if you like, I've seen the initialize.php and it looks simple to update.

[mitchins]

sorry meant to put this against the docker for TTRSS itself..