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* Change versioning scheme to make every feature/bug release a major number.
* Don't wake up every 20 milliseconds to check session management messages.
  Rather, wait for an event.
* Add --hide/--show, removed --hide-old. --hide and --show affect all pads
  on startup or can be used on an already running xpad instance. Patch by
  Jan Losinski.
* Update icon to be less aliased
* Relicense as GPL v3+