Add log file support (#1480)

Co-authored-by: ilike2burnthing <59480337+ilike2burnthing@users.noreply.github.com>

docker-compose.yml

@@ -7,9 +7,12 @@ services:
     container_name: flaresolverr
     environment:
       - LOG_LEVEL=${LOG_LEVEL:-info}
+      - LOG_FILE=${LOG_FILE:-none}
       - LOG_HTML=${LOG_HTML:-false}
       - CAPTCHA_SOLVER=${CAPTCHA_SOLVER:-none}
       - TZ=Europe/London
     ports:
       - "${PORT:-8191}:8191"
+    volumes:
+      - /var/lib/flaresolver:/config
     restart: unless-stopped