In #333, the non-optional field `disconnectsIfNotMatching` was removed
completely. Therefore, downgrading from 2.2.0 may lose profiles due to
the missing required field.
Mitigate the issue by restoring the field as optional, even if it's
unused, for the sake of not breaking profile serialization until the
2.2.0 release. Remove the deprecated field after that.
Extend the feature by also providing a complementary "include" policy,
i.e. activate the VPN _only_ on the specified networks. "Trusted
networks" was only providing the "exclude" counterpart, i.e. _except_
the specified networks.
Closes#119