[feature request] allow using multiple domains for GITLAB_HOST
Add a new environment variable GITLAB_HOST_ALIASES (GITLAB_EMAIL_FROM and GITLAB_EMAIL_REPLY_TO modified accordingly) to have a list of domains for the same git host. This would allow sharing the same server with multiple projects, with each using their own domains.
For example, I can share git.fosscommunity.in with git.smc.org.in, git.gnukhata.in, gitlab.debian.net etc. I can see it is set at runtime and I think with small tweak this can be done.