new: when VPN_GATEWAY is not set, try and find the VPN_IF_NAME gateway address
new: verify VPN_CT_NAME health status before doing any action at startup
fix: #8 - Passwords with special characters might fail auth on qBittorrent
improve: better handle and verify login on qBittorrent
misc: verify and fix some shellcheck warnings
update: Dockerfile - substitute ncat with netcat-openbsd
fix: data/start.sh - use correct command to validate connection to qBittorrent
fix: data/start.sh - always check if port is open on firewall (fixes issue when starting and VPN mapped port is already equal to configured, fw check was skipped)