mr/bisect-in-c-2, was Re: What's cooking in git.git (Jul 2020, #01; Mon, 6)

> * mr/bisect-in-c-2 (2020-04-23) 12 commits
>  - bisect--helper: retire `--bisect-autostart` subcommand
>  - bisect--helper: retire `--write-terms` subcommand
>  - bisect--helper: retire `--check-expected-revs` subcommand
>  - bisect--helper: reimplement `bisect_state` & `bisect_head` shell functions in C
>  - bisect--helper: retire `--next-all` subcommand
>  - bisect--helper: retire `--bisect-clean-state` subcommand
>  - bisect--helper: finish porting `bisect_start()` to C
>  - bisect--helper: reimplement `bisect_next` and `bisect_auto_next` shell functions in C
>  - bisect--helper: reimplement `bisect_autostart` shell function in C
>  - bisect--helper: introduce new `write_in_file()` function
>  - bisect--helper: use '-res' in 'cmd_bisect__helper' return
>  - bisect--helper: fix `cmd_*()` function switch default return
>
>  Rewrite of the remainder of "git bisect" script in C continues.
>
>  Expecting a response to reviews.
>  cf. <nycvar.QRO.7.76.6.2005230007260.56@tvgsbejvaqbjf.bet>