[config] Lowercase the FQDN we get from the OS (closes #5040345) Browsers convert the host name part of URLs to lowercase. This has the unfortunate effect of triggering various CORS error messages in CubicWeb (because the Origin: header will contain lowercase letters). As per RFC 4343, host name comparison should be case-insensitive. So let's put it in lowercase when we grab it from the host system. If admins put uppercase letters in "host" or "base-url" in their all-in-one.conf, then it's their fault.

etc/init.d
etc/cubicweb.d
etc/bash_completion.d
usr/bin
usr/share/doc/cubicweb-ctl
var/log/cubicweb
var/lib/cubicweb/backup
var/lib/cubicweb/instances