Remove py2 support

Change-Id: Ieeaeb3b8efcae004e94aea6c1d2703c9782a8650
Reviewed-on: https://forge.frm2.tum.de/review/c/sine2020/secop/playground/+/21320
Tested-by: Enrico Faulhaber <enrico.faulhaber@frm2.tum.de>
Reviewed-by: Enrico Faulhaber <enrico.faulhaber@frm2.tum.de>

bin/make_doc.py

@@ -21,7 +21,6 @@
 #
 # *****************************************************************************
 
-from __future__ import division, print_function
 
 import os
 from os import path

bin/secop-console

@@ -1,4 +1,4 @@
-#!/usr/bin/env python
+#!/usr/bin/env python3
 #  -*- coding: utf-8 -*-
 # *****************************************************************************
 #

bin/secop-gui

@@ -1,4 +1,4 @@
-#!/usr/bin/env python
+#!/usr/bin/env python3
 # pylint: disable=invalid-name
 #  -*- coding: utf-8 -*-
 # *****************************************************************************

bin/secop-server

@@ -1,4 +1,4 @@
-#!/usr/bin/env python
+#!/usr/bin/env python3
 #  -*- coding: utf-8 -*-
 # *****************************************************************************
 #