Log Message:
Update to 2.20:

01/01/2007  *** v2.20 ***

            - Added 'prune' feature for removing roms, disk and/or samples
            - Added 'incorporate' feature to assist in combining datafiles

30/12/2006  *** v2.19 ***

            - Internal change that only affects MAMEDiff (see note below)
            - Improved -dX modes (understands merging despite differing names)

17/10/2006  *** v2.18 ***

            - More intelligent DTD creation when saving in ListXML format
            - Added support for game/display (MAME v0.107)
            - Added support for game/input/control (MAME v0.107)
            - Added support for emulator/build (MAME+MESS v0.101u4 upwards)
            - Added support for driver/savestate (MAME v0.101u1 upwards)
            - Note: The above changes affect the tab delimited format!

16/07/2006  *** v2.17 ***

            - Fixed bug that caused the DatUtil -g and -r options to crash

11/07/2006  *** v2.16 ***

            - Fixed bug that messed up internal indices (affected crc matching)
            - More intelligent directory scanner (regarding samples and CHDs)
            - Removed 64MB file limit from directory scanner (reads 1MB blocks)