Move compose to the root, update docs and unify control (#93)

.env.example

@@ -0,0 +1,19 @@
+##
+# All environment variables defined here will only apply if you pass them
+# to the OpenProject container in docker-compose.yml under x-op-app -> environment.
+# For the examples here this is already the case.
+#
+# Please refer to our documentation to see all possible variables:
+#   https://www.openproject.org/docs/installation-and-operations/configuration/environment/
+#
+TAG=14-slim
+OPENPROJECT_HTTPS=false
+OPENPROJECT_HOST__NAME=localhost
+PORT=127.0.0.1:8080
+OPENPROJECT_RAILS__RELATIVE__URL__ROOT=
+IMAP_ENABLED=false
+DATABASE_URL=postgres://postgres:p4ssw0rd@db/openproject?pool=20&encoding=unicode&reconnect=true
+RAILS_MIN_THREADS=4
+RAILS_MAX_THREADS=16
+PGDATA="/var/lib/postgresql/data"
+OPDATA="/var/openproject/assets"