Sometimes users would get confused because an option they were looking
for was not mentioned on a subcommand's man page, and they had not
noticed that the main git-annex man page had a list of common options.
This change lets each subcommand mention the common options, similarly
to how the matching options are handled.
This commit was sponsored by Svenne Krap on Patreon.
Docs say vicfg can configure everything from git-annex branch,
so it ought to configure numcopies.
Note that commenting out existing numcopies does not unset it.
This commit was sponsored by Thom May on Patreon.
