SVGHMI: make a copy of tests/svghmi as test/svghmi_widget because too crowded since having pages for widget documentation. Strip those pages from tests/svghmi, so that it
is more light for regular testing.
#
# 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