modified build to use emconfigure to work with latest emsdk which no longer defines EMSCRIPTEN variable
modified build to use emconfigure to work with latest emsdk which no longer defines EMSCRIPTEN variable

csound/csound,csound/csound,csound/csound,csound/csound,ketchupok/csound,ketchupok/csound,ketchupok/csound,csound/csound,ketchupok/csound,csound/csound,csound/csound,csound/csound,ketchupok/csound,ketchupok/csound,ketchupok/csound,ketchupok/csound,csound/csound,ketchupok/csound,ketchupok/csound,csound/csound