feat: Transfer sites to Linux 🦭

[darcywong00]

Per @mcdurdin

We have a bit of a priority on this now because PHP is ceasing to support Windows... We don't need to change PHP version, and I think nearly all the pages should be fine without changes. Primary things I can see are:

• web.config -> .htaccess
• Any places where we have backslashes in paths need to be forward slashes. Not likely to be many of these.
• Consider downloadable file types, in case there are any issues there

I don't think we have any executables in use on the site.
Ubuntu version shouldn't be important, I hope -- just a reasonably recent one? It would be nice to be able to run them under Docker and/or Apache for Windows as well.

The sites that we need to transfer are:

• https://help.keyman.com
• https://keyman.com
• https://api.keyman.com (+ database)
• https://keymanweb.com
• https://s.keyman.com feat: Start updating site for Docker s.keyman.com#73
• Legacy sites:
  • https://blog.tavultesoft.com
  • https://keymankeyboards.com
  • https://r.keymanweb.com
  • https://tavultesoft.com

Reference
https://github.com/Azure/app-service-linux-docs/blob/master/Runtime_Support/php_support.md

(redacted) Some engineering documentation for @mcdurdin and @tim-eves

[darcywong00]

Jotting a list of TODO's for the keyman.com site:

• Apply permanent redirects
• keyboard redirects
• /.well-known/web.config
• Dockerize api.keyman.com and database, so we can use them locally for keyman.com
• RUN cp /usr/local/etc/php/php.ini-production /usr/local/etc/php/php.ini
• For validating /go links, create a Markdown test page of the links (along with comparison to live redirects)

Another TODO:

• Since it's hard to keep track of all the port numbers across the site, @mcdurdin asks to have another Docker image that listens and forwards local requests to the appropriate site