Typo in blinkstick --add-udev-rule

Support
#1

Script still runs fine but it crashes after successfully doing its job with

Traceback (most recent call last):
  File "/usr/bin/blinkstick", line 324, in <module>
    sys.exit(main())
  File "/usr/bin/blinkstick", line 230, in main
    print("Rule added to {0}").format(filename)
AttributeError: 'NoneType' object has no attribute 'format'

Line 230 should be:

print("Rule added to {0}".format(filename))

Also might be worth noting that if you don’t feel like rebooting you can also run these two commands:

sudo udevadm control --reload
sudo udevadm trigger

Or since the script has admin privileges anyway you might go ahead and run them and get that out of the way for the user.