Var to enable/disable debug logs

[madmath03]

:sparkles: Var to enable/disable debug logs to close #79

Startup and configuration errors are still displayed with DEBUG to false, but any proxied or redirected resources will not appear in the logs. This will allow to remove the driver: none when using docker-compose while still keeping privacy:

https://github.com/searx/searx-docker/blob/master/docker-compose.yaml:

  morty:
    container_name: morty
    image: dalf/morty
    hostname: morty
    restart: always
    ports:
      - 127.0.0.1:3000:3000
    networks:
      searx:
        ipv4_address: 10.10.10.5
    command: -listen 10.10.10.5:3000 -timeout 6 -ipv6
    environment:
      - DEBUG=false
      - MORTY_KEY=${MORTY_KEY}
    read_only: true
    cap_drop:
      - ALL

[madmath03]

@asciimoo Sure. Done.