Finished fixing Wx IDs abuse. There was still some wasted IDs because of wx.NewId calls in many places where it wasn't needed, and those IDs were not re-used. As a consequence Beremiz was making exception crashing after a few hours of intensive use.
#
# Dockerfile for wxPython3.0 running on python2.7
#
FROM python:2.7-stretch
RUN set -xe \
&& apt-get update \
&& apt-get install -y --no-install-recommends python-wxgtk3.0 python-matplotlib \
&& apt-get install -y --no-install-recommends python-xvfbwrapper xvfb \
&& apt-get clean