Dispose only if there's something to dispose

DATFromDir/DATFromDir.cs

@@ -456,15 +456,21 @@ namespace SabreTools
 				catch (InvalidOperationException)
 				{
 					encounteredErrors = true;
+					if (archive != null)
+					{
 						archive.Dispose();
 					}
+				}
 				catch (Exception ex)
 				{
 					_logger.Error(ex.ToString());
 					encounteredErrors = true;
+					if (archive != null)
+					{
 						archive.Dispose();
 					}
 				}
+			}
 
 			// Get a list of files including size and hashes
 			Crc32 crc = new Crc32();

SabreHelper/Logger.cs

@@ -11,7 +11,7 @@ namespace SabreTools.Helper
 	/// - Create log files by date
 	/// - Clean up log files if there are more than x number per program
 	/// - Allow for "triggerable" logging done on an interval (async)
-	/// - Log filtering?
+	/// - Log filtering? (#if debug?)
 	/// </remarks>
 	public class Logger
 	{