Prior to this change, a user had to manually install their own udev
rules on Linux if they wanted to access the joystick without having to
run as root. The most common usecase was on systems based on Debian,
where the user would be a member of the plugdev group, and they would
create their own rule to allow members of the group to write to the
joystick.
This change adds a validated udev rule to the distribution, so if the
user compiles from source and does a make install, the rule to allow
plugdev group members to access the joystick is installed.
nirenjan