Improve site-wide HTTP -> HTTPS redirection

[jayaddison]

Is your feature request related to a problem? Please describe.
For various sometimes obscure reasons, currently we have a configuration where inbound HTTP connections to RecipeRadar infrastructure are not terminated by us.

Given that infrastructure changes are occurring in #19 related to HTTP requests, this seems like a good time to note this deficiency and begin to plan improvements.

Describe the solution you'd like
RecipeRadar should terminate HTTP traffic and immediately redirect it to HTTPS on the same host (and path?).

Describe alternatives you've considered

• Google could potentially terminate HTTP for us; that's fine in principle but it would be most consistent for us to receive all the request traffic
• We could potentially negotiate additional ports / tunnels from our network infrastructure provider and begin handling and redirecting the HTTP traffic ourselves

[jayaddison]

✅ done.