docs: add a cmd.exe version of the cd snippet

[mataha]

Hello,

I would like to include a snippet that presents usage of git combined with onefetch in cmd.exe, as I felt Windows shells were heavily underrepresented on that front.

It is suited for use in AutoRun scripts (something akin to .bashrc or .bash_profile, but isn't enabled by default).

[spenserblack]

This is far beyond my knowledge of Windows cmd.exe, but LGTM 😆

[o2sh]

Hey @mataha, awesome script! Too bad that I can't add it to my $PROFILE as a PowerShell script, but thank you so much for sharing it 🙏. Your contribution is greatly appreciated! 👍

I'll let you address @spenserblack remark before merging it.

[mataha]

Re: your comment - this can be formatted, but every linebreak has to be escaped and the escape has to be in a context in which whitespace characters are not significant, otherwise indentation will cause an error:

@set LAST_REPOSITORY=

@doskey cd = @( ^
    if "$*"=="" ( ^
        chdir /d "%%USERPROFILE%%" ^
    ) else ( ^
        chdir /d $* ^
    ) ^
) ^&^& ( ^
    for /f "usebackq tokens=* delims=" %%i in ( ^
        `"@git rev-parse --show-toplevel 2$Gnul"` ^
    ) do @( ^
        if not "%%~i"=="" if not "%%~i"=="%%LAST_REPOSITORY%%" ( ^
            onefetch ^& set "LAST_REPOSITORY=%%~i" ^
        ) ^
    ) ^
)

Does it look better? Honestly, I don't know...

[o2sh]

otherwise indentation will cause an error

Yeah that's a shame. I think we can keep it as is 👍

Thanks for the effort though @mataha