• MenuWidgets: fix non translatable tool-tips
  
• MenuItems: add check for 'gnome-control-center.desktop'. Show a placeholder menu item if shortcut is invalid.
  
• Move appMenu to separate file.
  
• Clean up word clocks, weather widgets for Raven, Unity layouts.
  
• Remove Launcher layout
  
• Clean up some Dash to Panel integration code.
  
• Add "Override Menu Rise" setting.
  
• Rework Recent Apps Tracker.
  
• Protect against null category get_icon(). #222
  
• Remove 'actor' references.
  
• Change a few menu widgets to extend from St class.