NvServices refactoring (#120)

* Initial implementation of NvMap/NvHostCtrl

* More work on NvHostCtrl

* Refactoring of nvservices, move GPU Vmm, make Vmm per-process, refactor most gpu devices, move Gpu to Core, fix CbBind

* Implement GetGpuTime, support CancelSynchronization, fix issue on InsertWaitingMutex, proper double buffering support (again, not working properly for commercial games, only hb)

* Try to fix perf regression reading/writing textures, moved syncpts and events to a UserCtx class, delete global state when the process exits, other minor tweaks

* Remove now unused code, add comment about probably wrong result codes

Ryujinx.Core/OsHle/Services/Nv/NvMap/NvMapHandle.cs

@@ -0,0 +1,37 @@
+using System.Threading;
+
+namespace Ryujinx.Core.OsHle.Services.Nv.NvMap
+{
+    class NvMapHandle
+    {
+        public int  Handle;
+        public int  Id;
+        public int  Size;
+        public int  Align;
+        public int  Kind;
+        public long Address;
+        public bool Allocated;
+
+        private long Dupes;
+
+        public NvMapHandle()
+        {
+            Dupes = 1;
+        }
+
+        public NvMapHandle(int Size) : this()
+        {
+            this.Size = Size;
+        }
+
+        public long IncrementRefCount()
+        {
+            return Interlocked.Increment(ref Dupes);
+        }
+
+        public long DecrementRefCount()
+        {
+            return Interlocked.Decrement(ref Dupes);
+        }
+    }
+}