Add SF2 support for macOS (#3446)

* Add SF2 support for macOS

Closes #649

.travis/osx..install.sh

@@ -1,6 +1,6 @@
 #!/usr/bin/env bash
 
-PACKAGES="cmake pkgconfig fftw libogg libvorbis libsndfile libsamplerate jack sdl stk fluid-synth portaudio node fltk"
+PACKAGES="cmake pkgconfig fftw libogg libvorbis libsndfile libsamplerate jack sdl stk portaudio node fltk"
 
 if [ $QT5 ]; then
 	PACKAGES="$PACKAGES homebrew/versions/qt55"
@@ -10,4 +10,10 @@ fi
 
 brew install $PACKAGES
 
+# Recompile fluid-synth without CoreAudio per issues #649
+# Changes to fluid-synth.rb must be pushed to URL prior to use
+url=$(git remote get-url origin)
+branch=$(git symbolic-ref --short HEAD)
+brew install --build-from-source $url/raw/$branch/cmake/apple/fluid-synth.rb
+
 sudo npm install -g appdmg