libraries/aubio: Fix handling of the python{,3} bindings.

Signed-off-by: Matteo Bernardini <ponce@slackbuilds.org>

libraries/aubio/README

@@ -7,5 +7,7 @@ results too.
 
 jack-audio-connection-kit and ffmpeg are optional dependencies.
 
-To build the python bindings, pass BINDINGS=yes to the script:
-for these you need the additional dependency numpy.
+The python bindings are built if numpy is available and the python3
+ones are built if numpy3 is available: if both versions of python
+are present in the system, the aubio and aubiocut python scripts
+will use python3.

libraries/aubio/aubio.SlackBuild

@@ -60,7 +60,7 @@ set -e
 rm -rf $PKG
 mkdir -p $TMP $PKG $OUTPUT
 cd $TMP
-rm -rf $PRGNAM-$VERSION
+rm -rf $PRGNAM-$VERSION $PRGNAM-$VERSION-2
 tar xvf $CWD/$PRGNAM-$VERSION.tar.bz2
 cd $PRGNAM-$VERSION
 chown -R root:root .
@@ -93,10 +93,16 @@ CXXFLAGS="$SLKCFLAGS" \
 ./waf install \
   --destdir=$PKG
 
-if ! [ "${BINDINGS:-no}" = "no" ]; then
-  cd python
-    python setup.py install --root=$PKG
-  cd ..
+cd ..
+cp -a $PRGNAM-$VERSION $PRGNAM-$VERSION-2
+cd -
+
+if $(python -c 'import numpy' 2>/dev/null); then
+  python setup.py install --root=$PKG
+fi
+if $(python3 -c 'import numpy' 2>/dev/null); then
+  ( cd ../$PRGNAM-$VERSION-2
+    python3 setup.py install --root=$PKG )
 fi
 
 find $PKG -print0 | xargs -0 file | grep -e "executable" -e "shared object" | grep ELF \