[CM] Snd 8.9

[Bill Schottstaedt]

Snd 8.9

many more Forth and Ruby improvements from Mike.

three more fft windows: bohman-window, bartlett-hann-window, flat-top-window

kalman-filter-channel (dsp.scm) -- noise-reduction experiment

clean.scm -- more noise reduction (clean-channel|sound)

File:Close all menu if more than one sound open

open-file-dialog-directory to set the initial Open File dialog directory

changed default html reader from mozilla to firefox

added bindings to xg.c for cairo and gtk print

added a cairo graphics backend (on the --with-cairo configure switch)
  no "eye candy" yet, but everything works, I hope.
  

checked: Gauche 0.8.9, pango 1.15.6, 1.16.0|1, gsl 1.9, fth 1.0.8, sbcl 1.0.3,
    glib 2.12.10|11 2.13.0, cairo 1.4.0, gtk+-2.10.10


Thanks!: Michael Edwards, Peter Anderson, Immanuel Litzroth, Mike Scholz,
         Jay LaBoeuf, Max Mathews, Luke Dahl, Joanne Carey, Charles Turner,
	 Kjetil Matheussen, Anders Vinjar