[PATCH v3 0/6] worktree lock/unlock

v3 changes almost all patches so I didn't bother with interdiff

  [1/6] worktree.c: add find_worktree()

    This replaces the old find_wortree_by_path(). It now takes both prefix
    and command line argument so it can do some intelligent things with
    them if needed.

  [2/6] worktree.c: find_worktree() learns to identify worktrees by basename

    This is from Eric's suggestion. Here we only care about the "argument"
    argument and ignore the "prefix" argument from 1/6

  [3/6] worktree.c: add is_main_worktree()
 
    This is the only unchanged patch since v2!

  [4/6] worktree.c: retrieve lock status (and optionally reason) in get_worktrees()

    This used to be is_worktree_locked()

  [5/6] worktree: add "lock" command

    Besides Eric's comments in v2, the syntax line "worktree lock <path>"
    is changed to "worktree lock <worktree>", where <worktree> could be
    either a path, or a base name, or something more in future. I'm aware
    that we don't like showing "worktrees" in user documents, favoring
    working trees. But I think <worktree> is ok in this case.

  [6/6] worktree: add "unlock" command

    Pretty much addressing comments from v2 and some more changes because
    of the new 1/6 and 4/6.

 Documentation/git-worktree.txt         | 33 +++++++++++++----
 builtin/worktree.c                     | 66 ++++++++++++++++++++++++++++++++++
 contrib/completion/git-completion.bash |  5 ++-
 t/t2028-worktree-move.sh (new +x)      | 62 ++++++++++++++++++++++++++++++++
 worktree.c                             | 53 +++++++++++++++++++++++++++
 worktree.h                             | 14 ++++++++
 6 files changed, 226 insertions(+), 7 deletions(-)
 create mode 100755 t/t2028-worktree-move.sh