Environment variables to use .env instead of manually exporting it

[r0lodex]

[RushOnline]

There is just enough to mention service variable to set it from environment.

services:
  integram:
    environment:
      - INTEGRAM_INSTANCE_MODE=multi-main
      - INTEGRAM_CONFIG_DIR=/app/.conf
      # next variable values will be taken from .env
      - TZ
      - INTEGRAM_MONGO_URL
      - INTEGRAM_REDIS_URL
      - INTEGRAM_PORT
      - INTEGRAM_BASE_URL