Low level graphics API prerequisites (#319)

* Add GalPipelineState and IGalPipeline

* Separate UploadVertex call

* Add ConstBuffer cache

* Move Vertex Assembly into GalPipelineState

* Move Uniform binds to GalPipelineState

* Move framebuffer flip into a buffer

* Rebase

* Fix regression

* Move clear values from VertexEndGl to ClearBuffers

* Rename obscure names O->Old S->New

Ryujinx.HLE/Gpu/Memory/NvGpuBufferType.cs

@@ -5,6 +5,7 @@ namespace Ryujinx.HLE.Gpu.Memory
         Index,
         Vertex,
         Texture,
+        ConstBuffer,
         Count
     }
 }