install for python3 too. i2c_mutex requires it as the end user may be using python3

Author: CleoQc

install_script_tools.sh

@@ -50,5 +50,6 @@ fi
 cd $PIHOME/$DEXTER/$LIB/$DEXTER/$SCRIPT
 sudo apt-get install build-essential libi2c-dev i2c-tools python-dev libffi-dev -y
 python setup.py install
+python3 setup.py install
 
 popd > /dev/null