Fix: launchctl dubious permissions error

This simple patch fixes a file permissions error on Mac OS X (10.8 & 10.9) for the katon.plist file.
 
When trying:
    $ katon restart

reports the following error with the file permissions on the katon.plist file:

    $   launchctl: Dubious permissions on file (skipping): /Users/USERNAME/Library/LaunchAgents/katon.plist
    $   nothing found to unload

Hopefully it's useful.