[CM] CFFI for Csound5

[Michael Gogins]

I have committed to Csound 5 CVS csound5/interfaces/csound5.lisp. This is a 
Common Foreign Function Interface (CFFI) for the Csound 5 API. It replaces 
the earlier CLISP FFI-only interface, and should be more useful. I have 
removed the CLISP FFI file from CVS.

I have only very lightly tested this -- I only made sure that the 
csound5/examples/test.lisp would render "Trapped in Convert" on my PC. The 
example requires that Common Music and CFFI be installed for your LISP.

This no doubt needs more work, but I think this is the direction we should 
go, and what remains is to debug and extend csound5.lisp.

Regards,
Mike