Merge branch 'master' of https://github.com/j6t/git-gui

Merge branch 'master' of https://github.com/j6t/git-gui

* 'master' of https://github.com/j6t/git-gui:
  git-gui: silence install recipes under "make -s"
  git-gui: add gui and pick as explicit subcommands
  git-gui: check browser/blame arguments carefully
  git-gui: allow specifying path '.' to the browser
  git-gui: try harder to find worktree from gitdir
  git-gui: simplify [is_bare] to report if a worktree is known
  git-gui: use git rev-parse for worktree discovery
  git-gui: use rev-parse exclusively to find a repository
  git-gui: use --absolute-git-dir
  git-gui: do not change global vars in choose_repository::pick
  git-gui: guard set/unset of GIT_DIR and GIT_WORK_TREE
  git-gui: remove unnecessary 'cd $_gitworktree' from do_gitk
  git-gui: use HEAD as current branch when detached