Don't use these routines at present, one of them has a bug.

I just created a test suite which converts all 0-255 bytes to a byte array and then back again to a standard KiXtart integer arrary to make sure that the functions still work OK.

There is a problem with integers 128 - 159.

I'm not sure yet which of the routines is failing, though I've got a pretty good idead which one and why. I'll work on them as soon as I get some free time.