BUG: a CRC of 0 was written as 100...

src/main/java/de/mcs/tools/IntelHex.java

@@ -83,6 +83,7 @@ public class IntelHex {
     crc = crc & 0x00FF;
     crc = crc ^ 0x00FF;
     crc++;
+    crc = crc & 0x00FF;
     writer.append(String.format("%02X", crc));
     writer.append("\r\n");
     return crc;