[CM] Snd 20.8

[bil at ccrma.Stanford.EDU]

Snd 20.8:

Snd: removed gtk support
      Mike Scholz updated the Forth and Ruby scripts.

s7: s7_free
     a git repository: git at cm-gitlab.stanford.edu:bil/s7.git
                       https://cm-gitlab.stanford.edu/bil/s7.git

checked: sbcl 2.0.9

Thanks!: Tito Latini, James Hearon, Christos Vagias, Mike Scholz, 
Fernando