SVGHMI: rework Jump widget to cope with Enable Expressions.
Relative jumps are not disabled implicitely anymore when pointed HMI_NODE is 0.
Also, "activable()" implementation was enhanced to make it optional.
#!/usr/bin/env python
# -*- coding: utf-8 -*-
# This file is part of Beremiz
# Copyright (C) 2019: Edouard TISSERANT
#
# See COPYING file for copyrights details.
from __future__ import absolute_import
from svghmi.svghmi import *