core (sat.sh): force python 2 to launch twistd, and avoid launching wrong version if twistd is installed for python 3 too

src/sat.sh

@@ -3,6 +3,7 @@
 DEBUG=""
 DAEMON=""
 PYTHON="python2"
+TWISTD="$(which twistd)"
 
 kill_process() {
     # $1 is the file containing the PID to kill, $2 is the process name
@@ -103,4 +104,4 @@ if [ ! -d $log_dir ] ; then
     mkdir $log_dir
 fi
 
-exec twistd $MAIN_OPTIONS $ADDITIONAL_OPTIONS $APP_NAME_FILE
+exec $PYTHON $TWISTD $MAIN_OPTIONS $ADDITIONAL_OPTIONS $APP_NAME_FILE