Support Oreo's always blocking feature
We should investigate if there's any possibility to check if the user has enabled android's "Block Traffic if there's no working VPN" feature. If so, we should be able to disable the legacy mechanism that starts the VoidVPN.
We should also investigate if it is possible to exclude Bitmask itself from android's new Blocking feature so that the app can fetch the necessary provider configs via https before a working vpn connection gets set up.
Moreover we should give a recommendation in the app, that the user should enable the new shiny android feature.