Renamed the project to Umbraco.PublishedCache.NuCache - and move non NuCache related stuff to abstractions and infrastructure.

src/Umbraco.PublishedCache.NuCache/Snap/GenObj.cs

@@ -0,0 +1,37 @@
+using System;
+using System.Threading;
+
+namespace Umbraco.Web.PublishedCache.NuCache.Snap
+{
+    internal class GenObj
+    {
+        public GenObj(long gen)
+        {
+            Gen = gen;
+            WeakGenRef = new WeakReference(null);
+        }
+
+        public GenRef GetGenRef()
+        {
+            // not thread-safe but always invoked from within a lock
+            var genRef = (GenRef)WeakGenRef.Target;
+            if (genRef == null)
+                WeakGenRef.Target = genRef = new GenRef(this);
+            return genRef;
+        }
+
+        public readonly long Gen;
+        public readonly WeakReference WeakGenRef;
+        public int Count;
+
+        public void Reference()
+        {
+            Interlocked.Increment(ref Count);
+        }
+
+        public void Release()
+        {
+            Interlocked.Decrement(ref Count);
+        }
+    }
+}