Good question. I did a quick google and that didn't deliver an immediate answer. An old XP SP3 vm I have does have it, without me having ever installed it explicitly. Then again; it does have VS2012 installed, so it might have come along there.

So... either wait and see whether an issue comes up requesting support for it, or explicitly check whether the `powershell` command is available, and if not tell the user to either run the `install.bat` as admin, or that he must provide the `/NOADMIN` switch.

I have a tendency to go with the former (I don't think that there are any non-admin users on WinXP using LuaRocks), but have to run some more tests on the WinXP vm. What do you think?