GTK+ 3 added an Application API which allows an AppMenu to be added. This menu isn't part of the application's window, but on the status bar at the top of the screen.

Implement an AppMenu for GnomeSoy with the following options:

• Preferences
• About
• Quit

The Preferences option should open a new (blank for now) GTK+ dialog. The About option should open a dialog with a link to pysoy.org and a button to open the AGPLv3 license text.

While working on this task you should join and remain in #PySoy on Freenode to get help, feedback, and guidance from mentors and other developers. Code updates which may affect your work are also announced here as they happen.

When you've done, commit your work and post the resulting changeset url to this task.