Naming fixes.

Aaru.Images/SuperCardPro/Constants.cs

@@ -37,12 +37,12 @@ namespace Aaru.DiscImages
         /// <summary>SuperCardPro footer signature: "FPCS"</summary>
         const uint FOOTER_SIGNATURE = 0x53435046;
         /// <summary>SuperCardPro header signature: "SCP"</summary>
-        readonly byte[] scpSignature =
+        readonly byte[] _scpSignature =
         {
             0x53, 0x43, 0x50
         };
         /// <summary>SuperCardPro track header signature: "TRK"</summary>
-        readonly byte[] trkSignature =
+        readonly byte[] _trkSignature =
         {
             0x54, 0x52, 0x4B
         };