o Minor features (git scripts):
    - Make git-setup-dirs.sh create a master symlink in the worktree directory.
      Closes ticket 32347.
    - Add TOR_EXTRA_CLONE_ARGS to git-setup-dirs.sh for git clone
      customisation. Closes ticket 32347.
    - Add TOR_EXTRA_REMOTE_* to git-setup-dirs.sh for a custom extra remote.
      Closes ticket 32347.