Allow AddIn to detect framework of .NET Core assemblies correctly, if they are located in user's .nuget folder

ILSpy.AddIn/AssemblyFileFinder.cs

@@ -39,7 +39,7 @@ namespace ICSharpCode.ILSpy.AddIn
 
 		static readonly string DetectTargetFrameworkIdRefPathPattern =
 			@"(Reference Assemblies[/\\]Microsoft[/\\]Framework[/\\](?<1>.NETFramework)[/\\]v(?<2>[^/\\]+)[/\\])" +
-			@"|((NuGetFallbackFolder|packs)[/\\](?<1>[^/\\]+)\\(?<2>[^/\\]+)([/\\].*)?[/\\]ref[/\\])";
+			@"|((NuGetFallbackFolder|packs|.nuget[/\\]packages)[/\\](?<1>[^/\\]+)\\(?<2>[^/\\]+)([/\\].*)?[/\\]ref[/\\])";
 
 		public static string DetectTargetFrameworkId(Mono.Cecil.AssemblyDefinition assembly, string assemblyPath = null)
 		{