Add background starts option

[sha-265]

Is your feature request related to a problem? Please describe.

I'm using SSH port forwarding for some apps on my device, and I want to be able to start ConnectBot automatically when using this apps, and not manually start CB.

Describe the solution you'd like

Orbot have an option called "Background Starts" which allow apps to tell Orbot to start Tor and related services. I think it could be relevant in this case also.