Comment 6 for bug 1466951

I believe Juju sets the environment variables internally, and passes those values into charms, but probably doesn't set it in /etc/environment which means not all applications that are running will see them at the right time.

IMO, we should be doing

1) http-proxy, https-proxy, no-proxy are used as environment variables and configured into /etc/environment
2) apt-http-proxy, apt-https-proxy, apt-no-proxy are values that can be set but only affect /etc/apt/*.d/ configuration settings.