[arch-general] Fix or not fix? install scriptlets with user handling.

[ludovic coues]

A solution in pacman, getting rid of user adding in .install script,
can allow security like asking user to confirm creation of group and
user.

This would be a secure way of doing thing, and users/admin would be
aware of new user/group.

And like glenn, I'm wondering how package can add or remove daemon.
These are users set, and when are ok, need no worries. If package
add/remove them, it's unexpected problem coming to the user.