[CM] Building snd from source

[Bill Schottstaedt]

 >  ..but at least for a newbie it is a little confusing that provided
 >  functionality which comes with the archive should better not touched

The original idea was that snd_conffile.scm and Dave Phillips'
contributions were "suggestions" or examples of ways to do things,
and users would set up their own customizations, taking what
they liked from the examples.  But, these files aren't being used
that way, so at least the tutorial files need to be made more
robust.  I'll do that over the next few days.

(Actually all the Scheme/Ruby files started out in that spirit --
only the C side is intended to be bullet-proof).