move the stack catalogue out of the framework

stack/ and docker/ now live in the myos-stacks project (extracted with their
history). What the framework itself needs stays here:
- stack/myos/*.yml            -> share/compose/
- docker/myos/                -> share/docker/myos/
- docker/compose/             -> dropped, docker compose >= 2.24.4 is now required

Residues fixed along the way: DOCKER_IMAGES scanned a hardcoded ./docker,
include.mk filtered a hardcoded stack/*.mk, and docker-image-myos expanded an
undefined MYOS_DOCKER_IMAGES on every up/build.

README and CHANGELOG rewritten: they still documented make host,
host-certbot-* and user-config, all removed when the catalogue was split out.

spec/golden/expected/misc-help.txt

@@ -43,10 +43,10 @@ DOCKER_SOCKET_LOCATION /var/run/docker.sock
 DOCKER_SYSTEM Linux
 DOMAIN example.test
 APP myos
-APPS c411 dsh myos wbr wbr.old
-BRANCH lightning
-VERSION legacy-1.0-beta
+APPS @APPS@
+BRANCH @BRANCH@
+VERSION @VERSION@
 RELEASE
-COMPOSE_FILE @MYOS@/stack/myos/networks.yml
+COMPOSE_FILE @MYOS@/share/compose/networks.yml
 DOCKER_REPOSITORY tester/myos/local
 [exit 0]