YML -> Docker change minutes

* Present:
  + Rash, Kendy, Michael

* Issues:
  + Access from multiple domain changes:
    Access from multiple domains does not work. · Issue #4477 · CollaboraOnline/online · GitHub

* Thoughts on what to do:
  + an important change to avoid confusion between servers
    and their aliases etc.
  + we will add some better YAML support for docker
    pieces
  + keep the home-user with a domain=<something> working.

* Actions:
  + create a new perl script - perl is already a depdendency
    and start to kill yet-another-horror-shell-script this
    time called: start-collabora-online.sh

  + replace existing perl doing regexp substitution with a
    single invocation of this new perl script.

  + check if domain= is a simple, single host - and if so build
    an alias group for it - based on https:// and port 443

  + add aliasgroup1, aliasgroup2 env. variables to the YML,
    these include to comma separated series of aliased hosts

    eg.

  aliasgroup1=https://another\\.aliasgroup\\.de:443,https://\(still\|something\)\\.in\\.this\\.group.de:443,https://blablah
  aliasgroup2=https://\(aliasgroup\\.de|still\\.in\\.this\\.group.de\):443

  + add helpful example to alias_groups with https port numbers.

  + upgrade ~horrifying regular expressions to use standardized
    commented place-holders in the coolwsd.xml eg.

  "<!-- Docker substitute alias_groups -->"

  + hack out back-compat (but un-used when we have an alias)
    <host lines -> who-hoo!
    + support for this is only for legacy RPM systems.

  + adapt the home-use mode="first" to accept the first server
    without regard to the (now removed) random <host list.
    + if a bad-actor connects first, we won't be able to
      connect to our good server anyway, and will catch on
      upgrade testing.

  Gokay - I'd see this as a release blocker; can you track ?

  Kendy to have a skeleton of the perl script in ~3 hours.

  Rash to play building docker images.

  Thanks all,

    Michael.