Move archive constants

SabreTools.FileTypes/XZArchive.cs

@@ -15,6 +15,19 @@ namespace SabreTools.FileTypes
     /// </summary>
     public class XZArchive : BaseArchive
     {
+        #region Constants
+
+        /* (Torrent)XZ Header Format
+            https://tukaani.org/xz/xz-file-format.txt
+
+            00-05		Identification (0xFD, '7', 'z', 'X', 'Z', 0x00) XzSignature
+            06			Flags (0x01 - CRC32, 0x04 - CRC64, 0x0A - SHA-256)
+            07-0A		Flags CRC32 (uint, little-endian)
+        */
+        private readonly static byte[] TorrentXZHeader = new byte[] { 0xfd, 0x37, 0x7a, 0x58, 0x5a, 0x00, 0x01, 0x69, 0x22, 0xde, 0x36 };
+
+        #endregion
+
         #region Fields
 
         /// <summary>