Create separate files for internal skippers

SabreTools.Skippers/SkipperFiles/NintendoEntertainmentSystem.cs

@@ -0,0 +1,45 @@
+using System.Collections.Generic;
+
+namespace SabreTools.Skippers.SkipperFiles
+{
+    /// <summary>
+    /// SkipperFile for Nintendo Entertainment System headers
+    /// </summary>
+    /// <remarks>Originally from nes.xml</remarks>
+    internal class NintendoEntertainmentSystem : SkipperFile
+    {
+        public NintendoEntertainmentSystem()
+        {
+            // Create tests
+            var rule1Test1 = new SkipperTest
+            {
+                Type = HeaderSkipTest.Data,
+                Offset = 0x00,
+                Value = new byte[] { 0x4E, 0x45, 0x53, 0x1A },
+                Result = true,
+            };
+
+            // Create rules
+            var rule1 = new SkipperRule
+            {
+                StartOffset = 0x10,
+                EndOffset = null,
+                Operation = HeaderSkipOperation.None,
+                Tests = new List<SkipperTest>
+                {
+                    rule1Test1,
+                }
+            };
+
+            // Create file
+            Name = "Nintendo Famicon/NES";
+            Author = "Roman Scherzer";
+            Version = "1.1";
+            SourceFile = "nes";
+            Rules = new List<SkipperRule>
+            {
+                rule1,
+            };
+        }
+    }
+}