Add few clarifications to the README based on feedback

[goldyfruit]

• [x] OVOS_USER in the .env file
• [x] Use the --parallel option to avoid too high disk consumption during the up -d
• [x] Add information about how to use tts.list, phal.list/phal-admin.list and stt.list
• [x] Differences between docker-compose and docker compose commands
• [x] Restrict remote access to the message bus via IPTables
• [x] Mac OS procedure must be revised as sounddevice microphone plugin is now available
• [x] Add docker stats debug command