The mechanism to use parse-options API to automate the command line
completion continues to get extended and polished.
* nd/parseopt-completion-more:
completion: use __gitcomp_builtin in _git_cherry
completion: use __gitcomp_builtin in _git_ls_tree
completion: delete option-only completion commands
completion: add --option completion for most builtin commands
completion: factor out _git_xxx calling code
completion: mention the oldest version we need to support
git.c: add hidden option --list-parseopt-builtins
git.c: move cmd_struct declaration up