[CM] snd 5.12

[Bill Schottstaedt]

5.12 changes:

added contrib/DotEmacs thanks to Fernando.

many (optimizable) functions can now be treated as "virtual" editing
  operations -- ptree-channel (this is step 4 toward a virtual editor).

run macro for Snd.  Preliminary timing tests using with-sound (ws.scm)
  and v.scm indicate that Snd runs within a factor of 2 of the fully
  optimized CL/CLM speeds (ACL for example).

snd-pixel is now a no-op; Snd color variables use the xm-module type
  system, so snd-pixel can be deleted.
env-channel can take an envelope (list) arg.
bad-header-hook to handle bogus headers automatically in open-sound.
update-transform changed to update-transform-graph.
added sample-reader-position, mus-file-name, continue-sample->file.

Thanks to Stefan Schwandter, Sebastian Sauer, Fernando Lopez-Lezcano,
  Ludger Brummer, Michael Scholz for bug reports.

checked: gtkglext-0.3.2 (and 0.2.1), gcc 3.1, ladspa 1.1