- No more global variables
- Inject merged servers to configuration package
- Fix#566: configuration parsing to use persisted servers.json
- Move server data files from `internal/constants` to `internal/storage`
- `internal/wireguard` client package with unit tests
- Implementation works with kernel space or user space if unavailable
- `WIREGUARD_PRIVATE_KEY`
- `WIREGUARD_ADDRESS`
- `WIREGUARD_PRESHARED_KEY`
- `WIREGUARD_PORT`
- `internal/netlink` package used by `internal/wireguard`
- Move network protocol from ServerSelection to OpenVPNSelection child
- Move PIA encryption preset from ServerSelection to OpenVPNSelection child
- Move custom port from ServerSelection to OpenVPNSelection child
- Paves the way for Wireguard
- VPN struct contains Type, Openvpn and Provider configurations
- OpenVPN specific options (e.g. client key) moved from Provider to Openvpn configuration struct
- Move Provider configuration from OpenVPN configuration to VPN
- HTTP control server returns only openvpn settings (not provider settings)
