Add support for "old-style" Faust polyphony.
Makes the nvoices declaration in the Faust source work as usual. By these means a monophonic synthesizer with freq/gain/gate controls becomes a polyphonic one, maintaining separate dsp instances for each of the voices.
This isn't quite as efficient and flexible as pd-faustgen2's new polyphony implementation which keeps all voices in a single dsp (this continues to be available as well). But it is what is readily supported by most other Faust architectures, and thus provides better compatibility with existing Faust programs. It also facilitates porting Faust programs developed in pd-faustgen2 to other architectures. In particular, it's now much easier to compile the same program as a DAW plugin.
As usual, please check below for ready-made packages for Mac, Windows, and Ubuntu. The latter package should hopefully work on most modern x86_64 Linux systems, other builds for various Linux systems can be found on the OBS.