[BRLTTY] Alva.

[Mike Pedersen]

> Support has now been added to brltty for the Alva BC640/680 models.
> This has 
> required significant changes to brltty's Alva driver so, given that these 
> changes were made without access to an older Alva model, I'd appreciate it very 
> much if those of you who have older models, e.g. Satellite and ABT, could build 
> the latest development revision of brltty, give it a thorough test with your 
> Alva, and let me know the results.

I just tested this with an old ABT340.  Braille displays just as I would
expect and the touch cursors and thumb keys work just fine.  

Mike