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/Gpu/NvGpuFifoMeth.cs

@@ -0,0 +1,11 @@
+namespace Ryujinx.Core.Gpu
+{
+    enum NvGpuFifoMeth
+    {
+        BindChannel           = 0,
+        SetMacroUploadAddress = 0x45,
+        SendMacroCodeData     = 0x46,
+        SetMacroBindingIndex  = 0x47,
+        BindMacro             = 0x48
+    }
+}