[Coco] Workkng on fig Forth for 6809

[Joel Rees]

I'm working on converting an early fig Forth model for the 6800 to the
6809, just because I don't like the usual routes taken with other fig
models.

I have two paths, one uses the 6809 call architecture, calling leaf words
with jsr/rts. The other uses an optimized fig VM model, calling the leaf
words with a jump and returning by jumping back to NEXT.

Both are currently buggy. The NEXT model does not uet compile, and the RTS
model still has trouble with the disk emulation.

But, if anyone is interested in playing around with the buggy code, it's
here:

https://ja.osdn.net/projects/fig-forth-6809/scm/git/fig-forth-6809/