atempt on docker-compose.yml for sentry

docker-compose.yml

version: '2' 
services:
  redis:
    image: redis
    container_name: redis

  postgres:
    image: postgres
    environment:
      - POSTGRES_PASSWORD
      - POSTGRES_USER
    container_name: postgres

  upgrade:
    image: sentry
    environment:
      - SENTRY_SECRET_KEY
    links:
      - redis
      - postgres
    command: "-it upgrade"

  sentry:
    image: sentry 
    links:
      - redis
      - postgres
    ports:
      - "8081:9000"
    container_name: sentry

  sentry-cron:
    image: sentry
    links:
      - redis
      - postgres
    environment:
      - SENTRY_SECRET_KEY
    command: "sentry run cron"
  
  sentry-worker:
    image: sentry
    links:
      - redis
      - postgres
    environment:
      - SENTRY_SECRET_KEY
    command: "sentry run worker"