Re: [PATCH v8 0/4] worktree: Support `--orphan` when creating new worktrees

> While working with the worktree based git workflow, I realised that setting
> up a new git repository required switching between the traditional and
> worktree based workflows. Searching online I found a SO answer [1] which
> seemed to support this and which indicated that adding support for this should
> not be technically difficult.
>
> This patchset has four parts:
>   * adding `-B` to the usage docs (noticed during dev and it seemed too small
>     to justify a separate submission)
>   * adding a helper fn to simplify testing for mutual exclusion of options
>     in `t/t2400-worktree-add.sh`
>   * adding orphan branch functionality (as is present in `git-switch`)
>     to `git-worktree-add`
>   * adding an advise for using --orphan when `git worktree add` fails due to
>     a bad ref.
>
> Changes from v7:
>   * Changed test_wt_add_excl() to use `grep -E` instead of `grep -P` (2/4) [2][3].
>
> 1. https://stackoverflow.com/a/68717229/15064705/
> 2. https://lore.kernel.org/git/xmqq7cxxzefp.fsf@gitster.g/
> 3. https://lore.kernel.org/git/230109.86r0w328nu.gmgdl@evledraar.gmail.com/