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

[Klaus Knopper]

Dear list,

After Mario Lang from Debian Accessibility has almost convinced me of
the benefits of using brltty vs sbl, I just subscribed to this list.

I'm working on a project called "Audio Desktop Reference Implementation
and Networking Environment" (ADRIANE), which is supposed to give blind
computer beginners a good start into using the internet, and barrier
free usage of all the things you can do with a computer, without getting
too much in contact with the operating system, especially without having
to figure out what's a "shell" first. ;-)

http://knopper.net/knoppix-adriane/index-en.html

For this environment, which already works well on an installed Debian
system, we are currently using sbl as screen reader and braille driver,
because it is the only program that has all the features we need, which
are:

- Possibility to use the screenreader WITHOUT a braille display, by
  using hotkeys on the normal keyboard for navigating and speaking he
  screen content. This is he most imporant feature.

- Disconnect/reconnect of bluetooth-connected braille devices without
  restarting the screenreader.

- Profiles for different programs/environments that are automatically
  activated.

- Keyboard-operated cut&paste support between programs and consoles.

- Multiple language/pitch/speed/volume support for the sofware speech
  synthesizer (festival) to be activated by keyboard shortcuts.

Especially the possibility to use and operate the screenreader only by
keaboard is a MUST. I know that brltty is primarily designed as a driver
for braille devices, but since it is alread now a good screenreader, it
should be possible to implement a "keyboard braille device driver" that
can be used in parallel with an additional braille line, or standalone.

I have not used brltty extensively yet, so please excuse if some of
the requested features already exist. But apparently the keyboard
support is not done yet.

Since I have also added patches and improvements to sbl, I'm offering to
do some of the implementation by myself, if possible with coordination
and help by the more experienced brltty programmers, who could give me a
hint on where to add those features would fit best. And, maybe someone
is already working on this?

With kind regards
-Klaus Knopper