fix(deployments): fix broken config mount and expand env example

- Fix docker-compose.yaml: mount config.dev.yaml instead of nonexistent
  configs/config.yaml
- Add deployments/config.dev.yaml with Docker service names and dev
  defaults for zero-setup make docker-up
- Expand .env.example with all SILO_* and LDAP_* variables
- Update config.example.yaml hostnames to localhost with Docker comments
- Add deployments/config.docker.yaml to .gitignore (generated file)

.gitignore

@@ -29,6 +29,7 @@ Thumbs.db
 # Config with secrets
 config.yaml
 *.env
+deployments/config.docker.yaml
 
 # Python
 __pycache__/