explain how to archive a non-gitlab repo

organization and to the https://gitlab.torproject.org/ server, through

gitlite hooks.

## Archiving a repository

To archive a repository, it must first be deactivated by adding a

`pre-receive` hook, e.g. in:

    /srv/git.torproject.org/repositories/PROJECT.git/hooks/pre-receive 

The script should display some sort of warning and exit with an error,

for example:

    #!/bin/sh

    cat <<EOF

    This repository is deprecated and should not be used anymore.

    See this issue for details:

    https://gitlab.torproject.org/tpo/tpa/team/-/issues/9999999

    EOF

    exit 1

Then in Gitolite, the repository must be put "in the Attic", using a

patch that looks something like this:

```

 repo project/foo

     RW                                       = anarcat

-    config gitweb.category                   = Old category

-project/foo "The Tor Project" = "foo project"

+    config gitweb.category                   = Attic

+project/foo "The Tor Project" = "foo project (deprecated)"

 repo project/bar

     RW                                       = @jenkins-admins

```

The `description` file in the repository should also be updated

similarly.

Note that repos can also be migrated (and archived) to GitLab, see

[the GitLab migration procedure](gitlab/#how-to-migrate-a-git-repository-from-legacy-to-gitlab) for details.

## Admin details

git-rw runs on `cupani.torproject.org` and runs as the git user. Users in the