WIP breaking stuff: updating docker image build process for Python 3.6

This requires a new way to pass requirements.txt files to Docker (since
they now link to each other), as well as building Python ourselves (since
even Ubuntu 16.10 doesn't have a decent Python 3.6).

This is just a WIP commit, will be fixed soon(ish).

docker/3_run/run.docker

@@ -8,6 +8,8 @@ libapache2-mod-wsgi \
 libapache2-mod-xsendfile \
 libjpeg8 \
 libtiff5 \
+ffmpeg \
+rsyslog logrotate \
 nano vim curl \
 && rm -rf /var/lib/apt/lists/*