Use python2 explicitly when running the buildpack

Author: Ryan Moran

bin/detect

@@ -23,4 +23,4 @@
 BP=$(dirname $(dirname $0))
 export PYTHONPATH=$BP/lib
 VERSION=`cat $BP/VERSION`
-python $BP/scripts/detect.py $1 $VERSION
+python2 $BP/scripts/detect.py $1 $VERSION

bin/finalize

@@ -43,8 +43,9 @@ for env_var in $env_vars; do
 done
 
 export PYTHONPATH=$BP/lib
+unset PYTHONHOME
 
-python $BP/scripts/compile.py $BUILD_DIR $CACHE_DIR
+python2 $BP/scripts/compile.py $BUILD_DIR $CACHE_DIR
 
 pushd $BUILD_DIR/.profile.d > /dev/null
   for f in *; do mv "$f" "finalize_$f"; done

bin/release

@@ -23,4 +23,4 @@
 BP=$(dirname $(dirname $0))
 export PYTHONPATH=$BP/lib
 
-python $BP/scripts/release.py $1
+python2 $BP/scripts/release.py $1

bin/rewrite

@@ -1,4 +1,4 @@
-#!/usr/bin/env python
+#!/usr/bin/env python2
 
 # Licensed to the Apache Software Foundation (ASF) under one or more
 # contributor license agreements.  See the NOTICE file distributed with

bin/start

@@ -1,4 +1,4 @@
-#!/usr/bin/env python
+#!/usr/bin/env python2
 
 # Licensed to the Apache Software Foundation (ASF) under one or more
 # contributor license agreements.  See the NOTICE file distributed with