Add an initial stab at LR35902 (aka GameBoy) support. Untested and no disassembler though...

Signed-off-by: Adrian Conlon <Adrian.conlon@gmail.com>

LR35902/AbstractColourPalette.cs

@@ -0,0 +1,18 @@
+// <copyright file="AbstractColourPalette.cs" company="Adrian Conlon">
+// Copyright (c) Adrian Conlon. All rights reserved.
+// </copyright>
+namespace EightBit
+{
+    namespace GameBoy
+    {
+        public class AbstractColourPalette
+        {
+            private readonly uint[] colours = new uint[4];
+
+            protected AbstractColourPalette()
+            { }
+
+            public uint Colour(int index) => this.colours[index];
+        }
+    }
+}