* Postpone setting route gateway
Resolve in NetworkSettingsBuilder.
* Store routes separately from IP*Settings
Parse as optionals to avoid empty arrays.
* Deprecate routes stored in IP*Settings
* Apply routes from new fields
* Update CHANGELOG
Minimize target dependency on OpenSSL (easier to drop later).
Outside of OpenVPN tunnel extension, OpenSSL is only used to
decrypt encrypted private keys in CryptoContainer (found in
TunnelKitOpenVPNCore, therefore "temporarily" dependent on
CTunnelKitOpenVPNAppExtension for TLSBox/CryptoBox).
Davide De Rosa