(libnfc-less-bitutils-more-ponies) Get rid of bitutils.[hc] (part 1).

- New API function append_iso14443a_crc();
  - Add a PRINT_HEX macro for driver debugging (replaces print_hex function from bitutils.c);
  - Move bit-mirroring related functions to libnfc/mirror-subr.[hc];
  - Move iso14443 related functions to libnfc/iso14443-subr.c;
  - Move libnfc/bitutils.c hex-dumping code to examples/nfc-utils.c;
  - Replace calls to swap_endian32() and swap_endian64() functions with calls to bswap32() and bswap64 provided by endian.h.

And while I am here:
  - Fix the DBG macro so that it does not throw warning at compile time.

examples/nfc-poll.c

@@ -35,7 +35,6 @@
 #include <nfc/nfc.h>
 #include <nfc/nfc-types.h>
 #include <nfc/nfc-messages.h>
-#include "bitutils.h"
 #include "nfc-utils.h"
 
 #define MAX_DEVICE_COUNT 16