tests/src/io/test-sink_apple_audio.c: use aubio_source
ext/py-sink.c: do not generate
python/ext/py-{sink,source}.c: add close function
python/lib/aubio/slicing.py: use close not del, let garbage collector close the last file
src/io/*apple*: improve error messages
src/io/source{,_wavread}.c: improve error message
src/io/sink_wavwrite.c: add native basic wav writer
src/spectral/ooura_fft8g.c: use COS and SIN aliases