Need proxy support

[natejgardner]

This is a great plugin, but it's difficult to use in an enterprise environment since only internal urls can be reached without going through a proxy. Ideally, the underlying requests proxyDict can be set from the UI: http, https, ftp. Then the proxyDict can simply be passed if set for all underlying requests, allowing external urls to be reached.

[rikroe]

As this is also using requests, you could HTTP_PROXY, HTTPS_PROXY, NO_PROXY environment variables.
We set those via DSS_DATA_DIR/bin/env-site.sh. This will not only work for this plugin, but for all plugins/code using requests.

And if your proxy does SSL inspection, use REQUESTS_CA_BUNDLE to point to your system CA store (which of course should have your own CA in it).