Add custom check for ellipses "...", asking for replacement of "…".
Git ranges and the CLI wildcard matches are ignored.
This change includes fixes to all sites that did not pass the check.
The `--setup-signing` flag is a no-op when combined with `--existing`
and errors on bare repositories.
Make it effective in combination with `--existing` and also rewrite it
to support bare repositories, gracefully falling back to just avoid
writing to `.gitsigners`.
Fintan Halpenny
Lorenz Leutgeb