devel-warn: add 'warn-' to 'devel.empty-changegroup' config
Rename 'devel.empty-changegroup' to 'devel.warn-empty- changegroup' in order
to clarify it controls a warning message.
No alias is installed since the previous configuration option was not
documented.
@echo off
powershell -NoProfile -ExecutionPolicy unrestricted -Command "& '%~dp0\editmergeps.ps1' %*"