[PicForth] ANN: new module 'libbeep.fs'

[David McNab]

Hi,

Announcing a new PicForth module called 'libbeep.fs', for playing 
precise audio tones to an output pin.

Features:
  - 16-bit pitch and duration, for precise control
  - unlike smaller implementations, duration is not affected by pitch
  - offers words for playing portmento tones, ie where pitch slides up or
    down at a precisely controlled rate
  - has a 'rest' word, helpful for playing melodies

Download available on PicForth wiki:
  - http://wiki.enst.fr/bin/view/Picforth/Libbeepfs

Regarding this and my earlier contribs to wiki - I'm happy for them to 
stay on wiki, and/or to be absorbed into official PicForth distro - 
that's up to Samuel's preferences.

-- 
Cheers
David