Handle tor-powered apps in lockdown mode

In case the user has enabled Androids lockdown-mode (aka. the Android VPN system setting "Block connections without VPN"), tor-browser won't be able to connect, since it's excluded from the app list that is routed via the VPN.

This is not optimal, since it forces e.g. TorBrowser, Briar etc. users to turn off the lockdown-mode which in turn acts as a system wide kill switch.

We could try instead protect any socket connections coming from a particular application ID and I think these exempted connections should not affected by the lockdown mode.

Follow-up of #225 (closed)