Re: [PATCH 3/3] branch: add a --copy (-c) option to go with --move (-m)

> Add the ability to --copy a branch and its reflog and configuration,
> this uses the same underlying machinery as the --move (-m) option
> except the reflog and configuration is copied instead of being moved.
>
> This is useful for e.g. copying a topic branch to a new version,
> e.g. work to work-2 after submitting the work topic to the list, while
> preserving all the tracking info and other configuration that goes
> with the branch, and unlike --move keeping the other already-submitted
> branch around for reference.
>
> Like --move, when the source branch is the currently checked out
> branch the HEAD is moved to the destination branch. In the case of
> --move we don't really have a choice (other than remaining on a
> detached HEAD), but it makes sense to do the same for --copy.