[BRLTTY] typing braille from the PC keyboard

[Samuel Thibault]

Hello,

Coscell's question actually reminded me something I wanted to propose
before releasing brltty 4.0: adding support for typing braille dots from
the PC keyboard.

This can not be configured right now because it needs support for chords
rather that mere keypresses.

Then there is an additional concern: when typing braille, the
contraction table is not used for the translation. I know that there are
amiguities etc, but for instance brlkey
(http://coscell.molerat.net/brlkey-1.9.5.tar.bz2) copes with them for
chinese.  Maybe we'd need different tables for contracted output and
contracted input.

Samuel