[Amforth] Table driven CRC-8 generator/checker

[Enoch <ix...@ho...>]

Hello Matthias & all,

Please find in <http://pastebin.com/BRHaitj9> my complete CRC-8 implementation
for peer review and library inclusion if there is interest.

crc8.frt demonstrates how MARK can be used to reclaim the code space of table
generators via the persistence of data in PAD.

This CRC-8 implementation is more efficient than that of
lib/hardware/1wire-crc8.frt if messages are transmitted/recived on a
byte-by-byte basis.

Regards, Enoch.

PS1: Is there any reference implementation for [if] [else] [then]. I need them
and would be ready to help if needed.

PS2: I assumed that my amforth-shell.py patch was accepted :-)