Merge branch 'mr/worktree-list'

Add the "list" subcommand to "git worktree".

* mr/worktree-list:
  worktree: add 'list' command
  worktree: add details to the worktree struct
  worktree: add a function to get worktree details
  worktree: refactor find_linked_symref function
  worktree: add top-level worktree.c

diff --cc Makefile
Simple merge