[BRLTTY] brltty "keyboard braille device" support (and a few more things)

[Jason White]

I would like to add that I have used Yasr from time to time to access
console-based applications via speech. It is fairly full-featured, reliable,
and worth looking at before deciding to embark on another speech project
(whether as a BRLTTY extension or not).

Since obtaining a braille display for my laptop, I have been using it with
braille only, without even bothering to try to get speech working I used to
run software DECTALK on it, but this wasn't reliable.

I love braille displays.