[CM] Snd 24.7

[bil at ccrma.Stanford.EDU]

Snd 24.7:

s7: added complex-vectors. These are directly compatible with 
gsl_vector_complex.

   make-iterator's optional third argument can be #t which tells s7
   to choose the carrier based on the iterated sequence.

   s7_immutable has been deprecated, replaced by s7_set_immutable which
   has the necessary s7_scheme* argument.

   added s7_define_expansion.

checked: sbcl 2.4.8

Thanks!: Matthew