Texture/Vertex/Index data cache (#132)

* Initial implementation of the texture cache

* Cache vertex and index data aswell, some cleanup

* Improve handling of the cache by storing cached ranges on a list for each page

* Delete old data from the caches automatically, ensure that the cache is cleaned when the mapping/size changes, and some general cleanup

Ryujinx.Core/Gpu/Texture.cs

@@ -2,7 +2,7 @@ using Ryujinx.Graphics.Gal;
 
 namespace Ryujinx.Core.Gpu
 {
-    public struct Texture
+    struct Texture
     {
         public long Position { get; private set; }