lfs: add a repo requirement for this extension when converting to lfs
This covers both the vanilla repo -> lfs repo and largefiles -> lfs conversions.
The largefiles extension adds the requirement directly, because it has a
dedicated command to convert. Using the convert extension is better, because it
supports more features.
I'd like ideas about how to ensure that converting away from lfs works on all
files. (See comments in test-lfs.t)
@echo off
powershell -NoProfile -ExecutionPolicy unrestricted -Command "& '%~dp0\editmergeps.ps1' %*"