merge from develop

diff --cc src/aubio.h
index 226c59b,7a27567..b0d8ff8
--- 1/src/aubio.h
--- 2/src/aubio.h
+++ b/src/aubio.h
@@@ -184,7 -184,7 +184,8 @@@ extern "C
  #include "tempo/tempo.h"
  #include "io/source.h"
  #include "io/sink.h"
 +#include "io/audio_unit.h"
+ #include "synth/sampler.h"
  
  #if AUBIO_UNSTABLE
  #include "mathutils.h"