Only show latest version of addin from online gallery.

src/AddIns/Misc/AddInManager2/Project/Src/ViewModel/AvailableAddInsViewModel.cs

@@ -44,7 +44,8 @@ namespace ICSharpCode.AddInManager2.ViewModel
 
 		protected override IQueryable<IPackage> GetAllPackages()
 		{
-			return (ActiveRepository ?? AddInManager.Repositories.AllRegistered).GetPackages();
+			return (ActiveRepository ?? AddInManager.Repositories.AllRegistered).GetPackages()
+				.Where(package => package.IsLatestVersion);
 		}
 		
 		protected override IEnumerable<IPackage> GetFilteredPackagesBeforePagingResults(IQueryable<IPackage> allPackages)