For the past six months, all our mailing list sites have supported
HTTPS without incident. The main downside to the current
implementation is that Mailman itself writes some URLs with an
explicit scheme, causing people submitting forms from pages served
over HTTPS to get warnings because the forms are posting to plain
HTTP URLs for the same site. In order to correct this, we need to
tell Mailman to put https:// instead of http:// into these, but
doing so essentially eliminates any reason for us to continue
serving content over plain HTTP anyway.
Configure the default URL scheme of all our Mailman sites to use
HTTPS now, and set up permanent redirects from HTTP to HTTPS, per
the examples in the project's documentation:
https://wiki.list.org/DOC/4.27%20Securing%20Mailman%27s%20web%20GUI%20by%20using%20Secure%20HTTP-SSL%20%28HTTPS%29
Also update our testinfra functions to validate the blanket
redirects and perform all other testing over HTTPS.
Once this merges, the fix_url script will need to be run manually
against all lists for the current sites, as noted in that document.
Change-Id: I366bc915685fb47ef723f29d16211a2550e02e34