Salieri: shader cache (#1701)

Here come Salieri, my implementation of a disk shader cache!

"I'm sure you know why I named it that."
"It doesn't really mean anything."

This implementation collects shaders at runtime and cache them to be later compiled when starting a game.

Ryujinx.Common/Hash128.cs

@@ -0,0 +1,42 @@
+using System;
+using System.Runtime.InteropServices;
+
+namespace Ryujinx.Common
+{
+    [StructLayout(LayoutKind.Sequential)]
+    public struct Hash128 : IEquatable<Hash128>
+    {
+        public ulong Low;
+        public ulong High;
+
+        public override string ToString()
+        {
+            return $"{High:x16}{Low:x16}";
+        }
+
+        public static bool operator ==(Hash128 x, Hash128 y)
+        {
+            return x.Equals(y);
+        }
+
+        public static bool operator !=(Hash128 x, Hash128 y)
+        {
+            return !x.Equals(y);
+        }
+
+        public override bool Equals(object obj)
+        {
+            return obj is Hash128 hash128 && Equals(hash128);
+        }
+
+        public bool Equals(Hash128 cmpObj)
+        {
+            return Low == cmpObj.Low && High == cmpObj.High;
+        }
+
+        public override int GetHashCode()
+        {
+            return HashCode.Combine(Low, High);
+        }
+    }
+}