De-emphasize cmd.exe in readme

[casey]

cmd.exe is very fiddly, and Powershell is widely available, so recommend
Powershell over cmd.exe in the readme

[runeimp]

@casey why do you consider CMD fiddly? I prefer it over PowerShell in the vast majority of cases when I need to use Windows. Then again my computer experience started with DOS 3.2 so I'm quite used to it. I consider PS needlessly verbose in almost all cases. It's POSIX'ish using ls instead of dir but PS's version of ls is just horrible compared to ls on any version of BSD, Linux, or System V inspired system I've used. Not looking for you to defend your decision. I'm really curious on your thoughts. I'm sure most people that started with Windows that had PS available prefer it over CMD because it's so fancy. Also "Get off my lawn!" ;-)

[casey]

It's definitely a fair question!

I don't remember the details, but I remember that at one point I had extreme difficulty with quoting when using cmd.exe. This also came up in issue #743. I believe that in that issue, there wasn't really any way to get the desired behavior, due to differences in how cmd.exe quoting works when invoking cmd.exe from the terminal vs calling it directly from another process.

But, I don't use windows a ton, so I don't actually have that much first-hand experience.