[Suggestion] Change readme for udev ruled refer to /etc instead of /usr

[tutacat]

As the user is manually installing the rule (i.e. for flatpak or other portable installation), it would make more sense to use /etc.
/etc is for user managed settings, or changing default settings.
/usr is for package managed packages

Altered readme for this suggestion is available at #290 or tutacat/oversteer:patch-2