Add GNOME3 App Menu

[Jeremy Bícha]

Software Center developers should consider using the new GNOME3 App Menu. There are relatively few essential items in Software Center's menu (in my opinion at least) and using a simpler menu makes the program seem easier to use. Here's one suggested layout (note that the GNOME3 style usually avoids ellipses but that conflicts with the current Unity style):

Software Sources (or simply 'Preferences')
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Copy Web Link
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Turn On Recommendations… (changes to Turn Off Recommendations once enabled)
Sync Between Computers…
Reinstall Previous Purchases…
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Help
About Software Center
Terms of Use (perhaps should be moved inside About Software Center and Help)
For Software Developers
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Quit (or Close, Quit is more consistent with most other apps but Close may be better if apps are still being installed in the background)

I know that users of the Ubuntu GNOME Remix (13.04 will use Software Center by default) and users of Software Center on GNOME3 in Debian (or other distros) would appreciate this change and I believe it would be generally useful to Unity users too. It would definitely help make the app fit in better with other GNOME3 apps.

This would require us to port to GtkApplication first which I believe is a best practice now anyway.
http://developer.gnome.org/gtk3/stable/GtkApplication.html

ProblemType: Bug
DistroRelease: Ubuntu 13.04
Package: software-center 5.5.3
ProcVersionSignature: Ubuntu 3.8.0-1.5-generic 3.8.0-rc4
Uname: Linux 3.8.0-1-generic x86_64
ApportVersion: 2.8-0ubuntu2
Architecture: amd64
Date: Fri Jan 25 00:27:41 2013
MarkForUpload: True
PackageArchitecture: all
SourcePackage: software-center
UpgradeStatus: No upgrade log present (probably fresh install)

[dino99 (9d9)]

That version is no more maintained