Ugly, very ugly, incredibly ugly static linking of libsox on macOS

[reuben]

All of the brew installed dependencies have static libraries as well, but the macOS linker will always prefer a dynamic library if both exist under the same -L/foo -lbar resolution. The only way to force static linking is to include a full path to the static library. These changes basically reverse engineer the static library locations and then pass those to the linker.

[reuben]

All green. Dependencies from the macOS client now:

$ otool -L deepspeech
deepspeech:
	@rpath/libdeepspeech.so (compatibility version 0.0.0, current version 0.0.0)
	/System/Library/Frameworks/CoreAudio.framework/Versions/A/CoreAudio (compatibility version 1.0.0, current version 1.0.0)
	/usr/lib/libz.1.dylib (compatibility version 1.0.0, current version 1.2.11)
	/usr/lib/libc++.1.dylib (compatibility version 1.0.0, current version 400.9.4)
	/usr/lib/libSystem.B.dylib (compatibility version 1.0.0, current version 1252.200.5)